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Weight Training Injuries: Part 1: Diagnosing and Managing Acute Conditions
Ronald K. Reeves, MD; Edward R. Laskowski, MD; Jay Smith, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 2 - FEBRUARY 98

In Brief: When patients present with acute weight training injuries, familiarity with the demands of the activity can help physicians get the most out of the patient history. Probable risk factors for injury include errors in technique (described in a sidebar), skeletal immaturity, and anabolic steroid abuse. Common acute injuries in weight training include sprains, strains, tendon avulsions, and compartment syndrome. Possible nonmusculoskeletal problems include retinal hemorrhage, radiculopathy, and various cardiovascular complications. Treatment of acute musculoskeletal injuries varies, but usually includes sports medicine mainstays such as prompt RICE. Chronic weight training injuries will be described in part 2 of this series.

Over the past 20 years, the popularity of weight training has exploded. More than 45 million Americans train with weights regularly. Fortunately, serious injuries are relatively rare. In 1986, weight training injuries accounted for an estimated 43,400 emergency department visits out of a total of 5.6 million visits for all sports (1). In 1995, the last year for which statistics are available, emergency room visits for weight training injuries totaled 56,400, out of more than 5.4 million visits for all sports (2).

This article, the first of a two-part series, focuses on the diagnosis and treatment of acute weight training injuries. Part 2, to appear in an upcoming issue, will cover overuse and chronic conditions in weight lifters.

Out of the Circus
In the late 1800s, weight training was primarily the activity of circus strongmen. The first European weight lifting championship was held in Rotterdam in 1896, and the first world championship was in Vienna in 1898. In the first modern Olympics in 1896, Viggo Jensen and Launceston Elliot tied with lifts of 245 lb. The International Weightlifting Federation was founded in 1905, and since the 1970s the popularity of weight lifting has soared.

Though the popular image of a weight lifter is a bodybuilder such as Arnold Schwarzenegger or Lee Haney, most people who weight train do so as part of a comprehensive fitness program.

Weight Training Methods
There are several different styles of weight lifting/training. In this article the term "weight training" refers to exercises that use weight or resistance to build strength and muscle mass. The term "weight lifting" here refers to specific competitive activities such as Olympic lifting and power lifting. Though each style and method predisposes participants to a characteristic set of injuries, many injuries are common to all types of weight lifting/training.

The use of machines may be the most common method of fitness-related weight training at present. Machines allow exercisers to circuit train or to focus on individual muscles or muscle groups (eg, shoulders, hamstrings).

Circuit training.
Circuit training involves a rapid transition from one muscle-group exercise to the next with 15 to 30 seconds of rest between exercises. Participants use weights that are about 40% to 60% of their one-repetition maximum (1RM). Strength and aerobic gains from circuit training are modest--30% to 50% of the gains seen in dedicated strength or aerobic exercise regimens. The primary benefit of circuit training is the shorter workout time. Ballor et al (3) showed that alternating 15 seconds of exercise with 15 seconds of rest allows the greatest amount of work in the shortest time. This technique, when properly used, poses minimal risk of musculoskeletal injury, though the brief recovery time between exercises presents a risk for overuse injuries (1,4).

Focused weight training.
Focused weight training emphasizes specific muscle groups and can be performed with strength training machines or free weights; typically, both are used. Focused weight trainers usually lift weights as part of a comprehensive recreational fitness program. Training structure, loads, and training volumes vary. Focused weight trainers draw from other styles of weight training or competitive weight lifting and are at risk for acute and overuse injuries. Because training commonly produces discomfort, pain from overuse injuries is often misinterpreted as a normal result of the training. As in many other lifting styles, athletes often ignore the pain until performance suffers.

Bodybuilding.
Bodybuilding is exceedingly popular with younger people. The primary goal is to attain significant, symmetric muscle hypertrophy. Strength gains are secondary. Bodybuilding involves exhaustive workouts primarily involving free weights, using multiple sets and exercises and special training techniques for each muscle. Weight loads are frequently 80% to 100% of 1RM, with 1 to 12 repetitions. Special techniques are periodically used to alter training and facilitate consistent gains; examples include:

eccentric contractions or "negatives,"
forced repetitions to muscle failure,
supersets (rapidly paired exercises of different muscle groups in the same anatomic region), and
compound sets (rapidly matched exercises of the same muscle group).
Bodybuilders are at risk for both acute injuries (ie, from loss of control of a weight) and overuse injuries. Many turn to ergogenic agents such as anabolic steroids, human growth hormone, and nutrition supplements in an attempt to enhance training effects.

Olympic weight lifting.
Olympic weight lifting involves a single-repetition maximum lift in two exercises: the snatch and the clean and jerk (figure 1). The combined weight of the two lifts is the score in competition. Failure to observe proper technique in both lifts places athletes at risk for acute injuries from loss of control of the weight.

Power lifting.
Power lifting competitions involve three lifts: the squat, the bench press, and the dead lift (figure 2). As in Olympic lifting, the athlete seeks a single-repetition maximum in each exercise to generate a total score. Injuries in power lifting are similar to those seen in Olympic lifting, body building, and focused weight training.


Injury Rates and Risk Factors
Studies examining the incidence and types of weight training injuries report varying injury rates, but similar distributions of injury types (table 1: not shown).

Brown and Kimball (5) found that 39.4% (28 of 71) of adolescent power lifters entered in a teenage power lifting championship (ages 14 to 19) sustained injuries during training. The authors suggest that the high rate of injuries may have been from lack of supervision. Risser et al (6) in a retrospective survey observed that only 7.6% (27 of 354) of adolescent football players in a supervised weight training program sustained injuries, and Zemper (7) found only a 0.3% rate of weight training injuries in a 4-year study of a national sample of college football players who trained under supervision.

There are no risk-factor studies of weight training injuries, but poor technique, lack of supervision, skeletal immaturity, and steroid abuse are recognized as contributing factors (1,5,6). For a discussion of common weight training techniques that can cause injuries, see "Honing Technique to Avoid Injury," below.

Multiple cases of weight-training injuries associated with steroid abuse have been reported. The risks and benefits of these agents have been extensively reviewed elsewhere (8). In brief, steroids are classified as controlled substances by the US Food and Drug Administration, making steroid use other than for approved medical indications illegal. Though steroid abuse causes significant gains in strength and muscle mass, side effects may include acne, male pattern baldness, testicular atrophy, liver function abnormalities and hepatomas, myocardial ischemia, gynecomastia, hypertension, aggressiveness, and death (9). Steroids may cause physiologic changes in muscle, tendon, and ligaments, making them more susceptible to failure under load or repetitive use.

Steroid abuse has been associated with many acute injuries. Patients should be questioned regarding any history of such abuse. If individuals have such exposure, appropriate risk factor education and assistance with discontinuation should be offered.

Children's skeletal immaturity presents a particular risk for growth plate injuries from weight training. Therefore, the American Academy of Pediatrics has issued guidelines for weight training in children (10). These guidelines call for close supervision by knowledgeable trainers and medical professionals for children and adolescents who strength train and advise that adolescents reach Tanner stage 5 before participating in vigorous weight training.


Musculoskeletal Injuries
Though strains and sprains represent a large proportion of weight training injuries, they often do not come to medical attention unless the injury is particularly severe or symptoms are prolonged.

Ligament sprains.
Sprains cause pain, tenderness, and swelling at a ligament. The severity can be graded by the degree of laxity noted on examination. In general, a grade 1 sprain is painful without ligament laxity on examination, grade 2 lesions involve slight laxity, and grade 3 injuries feature gross instability.

1 Pain on palpation, solid end-point on examination (Pain on palpation, little or no weakness, no palpable defect or asymmetry)
2 Pain on palpation, mild laxity compared to contralateral ligament (Significant pain and mild weakness)
3* Significant laxity without a solid endpoint (Possible muscle asymmetry with a palpable defect, significant weakness)

Medial and lateral collateral knee ligament sprains may occur during squats, leg presses, and lunges with high loads or improper lower-extremity placement. Complete ligament disruption due to weight training is uncommon, but Freeman and Rooker (11) reported on a bodybuilder who had a history of steroid use and presented with a spontaneous anterior cruciate ligament rupture.

Most sprains and strains can be managed nonoperatively with protection, rest, ice, compression, and elevation (PRICE).

In addition to knee sprains, medial meniscus cartilage tears have been associated with knee flexion exercises (hamstring curls) and dead lifts (12).

Muscle strains and ruptures. The hallmarks of acute muscle strain are pain, muscle belly or myotendinous junction tenderness, limited range of motion, and relatively preserved strength . Grade 1 and grade 2 muscle strains are quite painful and are distinguished by the absence (grade 1) or presence (grade 2) of weakness. Hamstring muscle and low back (including paraspinal muscle) strains are particularly common among those who train with weights.

Muscle ruptures are essentially severe (grade 3) muscle strains. They are distinguished from strains by significant weakness and possibly a palpable muscle defect at the myotendinous junction. Tendon avulsions--disruption of the tendon-bone interface--are less common. In either injury, patients often report feeling a sudden "pop." Table 3 lists several reports of muscle ruptures and tendon avulsions in weight trainers. Steroid abuse was a factor in several of these injuries.

Muscle and Tendon Ruptures
Bilateral quadriceps muscle/tendon ruptures (29)*
Distal biceps brachii tendon avulsion (30)*
Patellar tendon rupture (31)
Pectoralis major muscle rupture (1)
Pectoralis major tendon avulsion (32)
Triceps tendon avulsion with radial neuropathy (33)*

Acute Fractures and Dislocations
Lunate dislocation (34)
Second rib fracture associated with bench press (35)
Talar dome fracture associated with squatting (36)

Acute Medical Events
Aortic dissection (24)*
Death (37,38)
Effort thrombosis (39)
External iliac artery stenosis (40)
Myocardial infarction (41,42)*
Pulmonary embolism (43)*
Spontaneous pneumothorax (44)
Stroke (45)*
Subarachnoid hemorrhage (23)
Tetraplegia (46)

*associated with anabolic steroid use.

In most instances, treatment is surgical repair or reattachment unless the lifter does not intend to return to his or her sport.

Pelvic avulsions. Avulsion of the anterior superior iliac spine (ASIS) is etiologically similar to a tendon avulsion; both are caused by excessive tension. In adolescents, the unfused ossifying iliac crest apophysis is relatively weak and susceptible to injury. Young weight trainers report a sudden pain and may feel a "pop" in the anterior pelvis when attempting forceful hip extension while the knee is flexed. This injury can also occur with lumbar hyperextension exercises and dead lifts (12). Typically, sartorius muscle contraction avulses the bony fragment. Examination reveals swelling and tenderness, and radiographs confirm the diagnosis.

Treatment is generally nonoperative, and most patients respond well to crutch ambulation and PRICE. Hip and lower-extremity strength training is initiated after symptoms subside. Some authors have reported success with open reduction and internal fixation (13,14).

Ischial apophysis and hamstring avulsions may also occur during weight training. Like ASIS avulsions, ischial apophysis avulsions occur in skeletally immature athletes and are most commonly associated with sprinting, running, or jumping activities (15). Weight training activities that can lead to ischial apophysis and hamstring avulsions include dead lifts, squats, and hamstring curls. The authors are unaware of any case reports of ischial apophysis avulsion injuries associated with weight training, though they may occur in skeletally immature athletes. Hamstring avulsions in adults have been reported.

Treatment is somewhat controversial, though ischial avulsion injuries can usually be managed nonoperatively. Orava and Kujala (16) reported their surgical experience with several cases of hamstring avulsions associated with dead lifts and squats. They recommend early surgical repair to prevent muscle contracture that may otherwise preclude anatomic reconstruction.

Acute fractures.
Fortunately, fractures account for only a small percentage of weight training injuries. The presentation may be acute and dramatic or chronic and insidious. Grumbs et al (17) reported on two adolescent boys who performed clean and jerk lifts; each lost control of the overhead weight and sustained bilateral radius or bilateral radius and ulna fractures. Reider et al (18) reported nonunion of a scaphoid fracture in a 17-year-old boy who developed wrist pain while attempting a 430-lb bench press 5 months before presentation. The patient did not seek immediate medical attention because he assumed the injury was merely a sprain.

Acute Medical Conditions
Various other uncommon medical conditions have been linked with weight training. Tremendous blood pressure elevations during maximal lifts may contribute to vascular injuries. Studies of blood pressures during weight lifting have reported readings as high as 480/350 mm Hg (19). MacDougall et al (20) also studied blood pressure responses in several lifting situations and found that blood pressure elevations were similar across contraction types (eccentric, concentric, isometric) when intensity was controlled. Narloch and Brandstater (21) demonstrated that slow exhalation during the strain phase of a lift significantly reduces blood pressure elevation. Thus, avoiding Valsalva's maneuvers during weight lifting may help limit blood pressure elevations.

Retinal hemorrhages cause acute unilateral changes in vision and typically resolve without surgical intervention (22). Subarachnoid hemorrhage and stroke are rare, but patients who have known aneurysms and bleeding risks should be advised to avoid heavy weight training (23). Many of the vascular complications noted in table 3 were associated with steroid abuse, which may be a more significant risk factor than weight training itself.

In four aortic dissections described by de Virgilio et al (24), two patients had a history of steroid abuse and hypertension. All four patients had cystic degeneration of the aortic media, but it is unknown if this was related to weight training or to an unidentified factor such as occult hypertension or unrecognized Marfan syndrome.

Rhabdomyolysis and acute compartment syndromes of the limbs have been reported by several authors (25,26). Clinical suspicion of compartment syndrome should be high when patients present with progressively severe muscle pain following strenuous workouts, especially if eccentric exercises were involved. The cardinal signs of acute compartment syndromes are pain and pressure in a muscle or muscle compartment, pain with stretching of that muscle, paresis, and paresthesias. A pulse may or may not be palpable. Compartment pressures should be measured when this condition is suspected. However, compartment syndrome is a clinical diagnosis based on the examination and the patient's overall medical status. Fasciotomy for pressure relief must be performed in a timely fashion to minimize permanent nerve and muscle injury.

Rhabdomyolysis in isolation or due to compartment syndrome can be life threatening because of the potential for acute renal failure and electrolyte abnormalities. Creatine kinase elevations to 76,000 IU/L have been reported (26). Treatment involves aggressive hydration, urine alkalization, and brisk diuresis.

Since acute radiculopathies are often associated with heavy lifting, many assume that weight lifters are at increased risk for radiculopathy. Certainly, acute radiculopathy can occur during weight training, and Jordan et al (27) have reported three patients who developed acute cervical radiculopathies while training. In an epidemiologic study of possible risk factors for cervical and lumbar disc herniation, Mundt et al (28) did find a possible association between free weight training and cervical radiculopathy (relative risk, 1.87; 95% confidence interval, 0.74 to 4.74). They found no increased risk for lumbar disc herniation.

Weight Training Awareness
Knowing weight lifting methods and the demands of the sport can make the patient history more productive. A detailed history and physical examination often leads to a narrow, focused differential diagnosis. Part 2 of this series will cover the diagnosis and treatment of chronic conditions that can result from weight training, including stress fractures, chronic degeneration of the spine, and weight lifter's headache.

Physicians who get to know the culture of weight training can ensure that their patients get the most benefit from the activity in the safest possible way.

references to follow

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References
Mazur LJ, Yetman RJ, Risser W: Weight-training injuries: common injuries and preventative methods. Sports Med 1993;16(1):57-63
National Electronic Injury Surveillance System: 1995 summary on injuries caused by weight lifting and sports. US Consumer Products Safety Commission, Washington DC, 1997
Ballor DL, Becque MD, Marks CR, et al: Physiologic responses to nine different exercise/rest protocols. Med Sci Sports Exer 1989;21(1):90-95
Namey TC, Carek JC: Power lifting, weight lifting, and bodybuilding. In Fu FH, Stone DA (eds): Sports Injuries: Mechanisms, Prevention, Treatment. Baltimore, Williams & Wilkins, 1994, pp 515-529
Brown EW, Kimball RG: Medical history associated with adolescent powerlifting. Pediatrics 1983;72(5):636-644
Risser WL, Risser JM, Preston D: Weight-training injuries in adolescents. Am J Dis Child 1990;144(9):1015-1017
Zemper ED: Four-year study of weight room injuries in a national sample of college football teams. NSCA Journal 1990;12(3):32-33
Ghaphery NA: Performance-enhancing drugs. Orthop Clin North Am 1995;26(3):433-442
Dickerman RD, Schaller F, Prather I, et al: Sudden cardiac death in a 20-year-old bodybuilder using anabolic steroids. Cardiology 1995;86(2):172-173
American Academy of Pediatrics Committee on Sports Medicine: Strength training, weight and power lifting, and body building by children and adolescents. Pediatrics 1990;86(5):801-803
Freeman BJ, Rooker GD: Spontaneous rupture of the anterior cruciate ligament after anabolic steroids. Br J Sports Med 1995;29(4):274-275
Brady TA, Cahill BR, Bodnar LM: Weight training-related injuries in the high school athlete. Am J Sports Med 1982;10(1):1-5
Veselko M, Smrkolj V: Avulsion of the anterior-superior iliac spine in athletes: case reports. J Trauma 1994;36(3):444-446
Thanikachalam M, Petros JG, O'Donnell S: Avulsion fracture of the anterior superior iliac spine presenting as acute-onset meralgia paresthetica. Ann Emerg Med 1995;26(4):515-517
Kujala UM, Orava S, Karpakka J, et al: Ischial tuberosity apophysitis and avulsion among athletes. Int J Sports Med 1997;18(2):149-155
Orava S, Kujala UM: Rupture of the ischial origin of the hamstring muscles. Am J Sports Med 1995;23(6):702-705
Grumbs VL, Segal D, Halligan JB, et al: Bilateral distal radius and ulnar fractures in adolescent weight lifters. Am J Sports Med 1982;10(6):375-379
Reider B, Yurkofsky J, Mass D: Scaphoid waist fracture in a weight lifter: a case report. Am J Sports Med 1993;21(2):329-331
MacDougall JD, Tuxen D, Sale DG, et al: Arterial blood pressure response to heavy resistance exercise. J Appl Physiol 1985;58(3):785-790
MacDougall JD, McKelvie RS, Moroz DE, et al: Factors affecting blood pressure during heavy weight lifting and static contractions. J Appl Physiol 1992;73(4):1590-1597
Narloch JA, Brandstater ME: Influence of breathing technique on arterial blood pressure during heavy weight lifting. Arch Phys Med Rehabil 1995;76(5):457-462
Pitta CG, Steinert RF, Gragoudas ES, et al: Small unilateral foveal hemorrhages in young adults. Am J Ophthalmol 1980;89(1):96-102
Haykowsky MJ, Findlay JM, Ignaszewki AP: Aneurysmal subarachnoid hemorrhage associated with weight training: three case reports. Clin J Sport Med 1996;6(1):52-55
de Virgilio C, Nelson RJ, Milliken J, et al: Ascending aortic dissection in weight lifters with cystic medial degeneration. Ann Thorac Surg 1990;49(4):638-642
Bird CB, McCoy JW Jr: Weight-lifting as a cause of compartment syndrome in the forearm: a case report. J Bone Joint Surg (Am) 1983;65(3):406
Bolgiano EB: Acute rhabdomyolysis due to body building exercise: report of a case. J Sports Med Phys Fitness 1994;34(1):76-78
Jordan BD, Istrico R, Zimmerman RD, et al: Acute cervical radiculopathy in weight lifters. Phys Sportsmed 1990;18(1):73-76
Mundt DJ, Kelsey JL, Golden AL, et al: An epidemiologic study of sports and weight lifting as possible risk factors for herniated lumbar and cervical discs: The Northeast Collaborative Group on Low Back Pain. Am J Sports Med 1993;21(6):854-860
David HG, Green JT, Grant AJ, et al: Simultaneous bilateral quadriceps rupture: a complication of anabolic steroid abuse. J Bone Joint Surg (Br) 1995;77(1):159-160
Visuri T, Lindholm H: Bilateral distal biceps tendon avulsions with use of anabolic steroids. Med Sci Sports Exerc 1994;26(8):941-944
Munshi NI, Mbubaegbu CE: Simultaneous rupture of the quadriceps tendon with contralateral rupture of the patellar tendon in an otherwise healthy athlete. Br J Sports Med 1996;30(2):177-178
Liu J, Wu JJ, Chang CY, et al: Avulsion of the pectoralis major tendon. Am J Sports Med 1992;20(3):366-368
Stannard JP, Bucknell AL: Rupture of the triceps tendon associated with steroid injections. Am J Sports Med 1993;21(3):482-485
Miller SJ, Smith PA: Volar dislocation of the lunate in a weight lifter. Orthopedics 1996;19(1):61-63
Goeser CD, Aikenhead JA: Rib fracture due to bench pressing. J Manipulative Physiol Ther 1990;13(1):26-29
Mannis CI: Transchondral fracture of the dome of the talus sustained during weight training. Am J Sports Med 1983;11(5):354-356
Dickerman RD, Schaller F, Prather I, et al: Sudden cardiac death in a 20-year-old bodybuilder using anabolic steroids. Cardiology 1995;86(2):172-173
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Cohen GS, Braunstein L, Ball DS, et al: Effort thrombosis: effective treatment with a vascular stent after unrelieved venous stasis following a surgical release procedure. Cardiovasc Intervent Radiol 1996;19(1):37-39
Khaira HS, Awad RW, Aluwihare N, et al: External iliac artery stenosis in a young bodybuilder. Eur J Vasc Endovasc Surg 1996;11(4):499-501
Appleby M, Fisher M, Martin M: Myocardial infarction, hyperkalaemia and ventricular tachycardia in a young male body-builder. Int J Cardiol 1994;44(2):171-174
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Gaede JT, Montine TJ: Massive pulmonary embolus and anabolic steroid abuse (letter). JAMA 1992;267(17):2328-2329
Simoneaux SF, Murphy BJ, Tehranzadeh J: Spontaneous pneumothorax in a weight lifter: a case report. Am J Sports Med 1990;18(6):647-648
Frankle MA, Eichberg R, Zachariah SB: Anabolic androgenic steroids and a stroke in an athlete: case report. Arch Phys Med Rehabil 1988;69(8):632-633
Shea JM: Acute quadriplegia following the use of progressive resistance exercise machinery. Phys Sportsmed 1986;14(4):120-124

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Honing Technique to Avoid Injury

Most patients who work out with weights do either circuit training or focused strengthening of specific muscle groups. To help them improve their form, avoid injury, and get the most from their workouts, it's a good idea to advise them about five common mistakes and safer alternative techniques.

Technique 1: Latissimus Dorsi Pull-Down
Problem: When the weight is lowered behind the neck, this exercise excessively flexes the cervical spine and loads the shoulders at the extreme of external rotation. The line of pull does not oppose the muscle fibers of the latissimus dorsi, and this does not maximally challenge the muscle. The behind-the-neck position increases the load on the cervical disks and the risk of spinous process fracture. The exercise puts the shoulder at a mechanical disadvantage that may contribute to rotator cuff injury or anterior shoulder instability. An excessively wide grip on the bar should also be avoided because it may increase shear forces across the glenohumeral joint.

Solution: The safer way to perform the exercise is to sit or kneel on one knee, lean back slightly at the hips, grip the bar slightly wider than shoulder width, and pull it down in front of the head.

Another exercise that effectively challenges the latissimus dorsi is seated rowing, an activity that minimizes shear force at the shoulder.


Technique 2: Knee Extension
Problem: Knee extensions are examples of open-kinetic-chain exercises, which isolate a particular muscle group--in this case, the quadriceps--and involve motion distal to the axis of the joint. During knee extensions, potentially damaging tibiofemoral shear forces are greater during the last 5° to 10° of extension and also if one "hyperextends" the knee. In addition, at the extremes of knee flexion (greater than 60°), increased patellar compression is potentially harmful (1,2).

Solution: Avoid "hyperextension" of the knee at the completion of knee extension, and train in a range that avoids extremes of knee flexion and extension, especially as the load is increased. Also, try to incorporate closed-kinetic-chain exercises, which involve predictable coordinated muscle contractions with motion at multiple joints in a limb whose segment meets fixed or constrained resistance.

Squats and leg presses can each be closed-kinetic-chain exercises, and shear force is generally less with these exercises, though a recent study (3) suggests that strain on the anterior cruciate ligament (ACL) is simmilar in both open- and closed-chain exercises.


Technique 3: Bench Press and Chest Fly
Problem: Hyperextension of the shoulders during bench press or chest fly exercises (dropping the elbows below or behind the plane of the body) places the pectoralis muscles at a mechanical disadvantage, contributes to glenohumeral instability through repetitive shoulder capsule trauma, and places excessive traction on the acromioclavicular joints (4).

Solution: The preferred way to perform the exercises is to adjust the exercise machine or starting position so that the elbows are even with or above the frontal plane when beginning the lift and during repetitions.


Technique 4: Military Press
Problem: Extreme shoulder external rotation and abduction during behind-the-neck military presses stress the shoulder capsule and inferior glenohumeral ligament, which can cause anterior shoulder instability (5,6). Extreme cervical flexion puts patients at risk for spinous process fracture and neck strains.

Solution: The safer way to do military presses is to lift the weight in front of the neck.


Technique 5: Squats
Problem: In a deep squat, when the thighs are parallel to the floor or lower, there is an excessive amount of shear load on the knee in a position in which the articular cartilage is thinnest. Descending to this position is done by power lifters who must meet technical specifications during competition, but they also place themselves at risk of cartilage damage.

Solution: Weight lifters should avoid deep squats and extremes of hyperflexion and hyperextension, and they should maintain lumbar spine stability during squat lifts.

References
Beynnon BD, Fleming BC, Johnson RJ, et al: Anterior cruciate ligament strain behavior during rehabilitation exercises in vivo. Am J Sports Med 1995;23(1):24-34
Palmitier RA, An KN, Scott SG, et al: Kinetic chain exercise in knee rehabilitation. Sports Med 1991;11(6):402-413
Beynnon BD, Johnson RJ, Fleming BC, et al: The strain behavior of the anterior cruciate ligament during squatting and active flexion-extension: a comparison of an open and a closed kinetic chain exercise. Am J Sports Med 1997;25(6):823-829
Wolfe SW, Wickiewicz TL, Cavanaugh JT: Ruptures of the pectoralis major muscle: an anatomic and clinical analysis. Am J Sports Med 1992;20(5):587-593
Gross ML, Brenner SL, Esformes I, et al: Anterior shoulder instability in weight lifters. Am J Sports Med 1993;21(4):599-603
Neviaser TJ: Weight lifting: risks and injuries to the shoulder. Clin Sports Med 1991;10(3):615-621

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Weight Training Injuries: Part 2: Diagnosing and Managing Chronic Conditions
Ronald K. Reeves, MD; Edward R. Laskowski, MD; Jay Smith, MD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 26 - NO. 3 - MARCH 98

This is the second of two articles on weight training injuries. The first, on acute injuries.

In Brief: The repetitive nature of weight training and the often heavy loads involved provide fertile ground for chronic injuries. Common chronic injuries include rotator cuff tendinopathy and stress injuries to the vertebrae, clavicles, and upper extremities. In addition, muscle hypertrophy, poor technique, or overuse can contribute to nerve injuries such as thoracic outlet syndrome or suprascapular neuropathy. Chronic medical conditions that are known to occur in weight trainers include vascular stenosis and weight lifter's cephalgia. Management of chronic problems will vary by condition, but relative rest and correction of poor technique are important for many.

Excessive weight training or the use of improper training techniques--or a combination of both--can lead to chronic injuries in weight trainers. Diagnosing chronic weight training injuries can be a challenge because the connection between patients' symptoms and weight training practices often aren't as obvious as, for example, runners' symptoms and their sport.

However, a familiarity with the spectrum of weight training injuries and an awareness of how improper techniques contribute to specific injuries will help physicians recognize such injuries and treat patients efficiently. It is important for physicians to understand proper technique so that they can instruct their patients accordingly.


Tendon and Ligament Injuries
There are relatively few data on the incidence of overuse injuries in weight lifting. Tendinitis, probably the most common overuse injury seen in weight training, accounts for 3.5% to 12% of weight training injuries (1-3). Chronic excessive stress on a tendon during weight training can overload tissues; using incorrect technique can also cause overuse injuries.

Rotator cuff injury.
Several weight training exercises, including the upright row, military press, and use of "pectoral deck" machines, jeopardize the muscles and tendons of the rotator cuff (see "Weight Training Injuries, Part 1: Diagnosing and Managing Acute Conditions"). Among the rotator cuff tendons, the supraspinatus tendon is the most frequently involved, probably because of its relative hypoperfusion and location in a potentially narrowed space below the acromion. Though rotator cuff injury is more common in people over age 40, it must be considered when a younger weight lifter or thrower presents with shoulder pain.

Patients may report diffuse aching shoulder pain that sharpens with overhead activity. Frequently, anterior chest and shoulder muscle development is disproportionate to that of the scapular stabilizers. The resultant inability of the periscapular muscles to stabilize the scapula leads to scapulothoracic and glenohumeral dysfunction and dyskinesia, which contributes to inefficient force transfer through the shoulder.

Management is largely nonoperative and entails modalities such as ice massage for pain control, shoulder range-of-motion exercises, stretching (with emphasis on the posterior capsule), and strengthening of the scapular stabilizers, posterior shoulder muscles, and external rotators.

Anterior shoulder instability.
Anterior instability of the shoulder can also be chronic during weight training. Several errors of technique can contribute to anterior instability: Behind-the-neck latissimus dorsi pull-downs load the shoulder at the extreme of external rotation; shoulder hyperextension during the bench press produces repetitive shoulder capsule trauma and places excessive traction on the acromioclavicular (AC) joint; and behind-the-neck military presses stress the shoulder capsule, the rotator cuff, and the inferior glenohumeral ligament (4,5).

The patient may report vague symptoms such as a feeling of looseness of the shoulder or transient numbness of the arm. Instability tests, including the apprehension test and the relocation test, should be done. The apprehension test involves passively moving the shoulder toward 90° of external rotation while the arm is abducted to 90°. A feeling of "impending dislocation," not to be confused with posterior shoulder pain caused by rotator cuff injury, signifies anterior instability. Pushing the humeral head posteriorly (the relocation test) will often relieve the symptoms of apprehension, and external rotation may be increased.

Treatment of anterior shoulder instability is still somewhat controversial. Most would advocate aggressive rehabilitation involving scapular stabilization and posterior deltoid and external rotator strengthening to prevent future dislocations. In an overhead-throwing athlete or high- shoulder-demand athlete, however, a case can be made for early evaluation for consideration of surgical repair.


Skeletal Disorders

Atraumatic osteolysis of the distal clavicle. Cahill (6) was the first to describe a series of weight trainers who developed atraumatic osteolysis of the distal clavicle. Hyperextension of the shoulder during the bench press (ie, dropping the elbows below the body line during the eccentric phase of the press) excessively stresses the AC joint and may contribute to pathogenesis.

Patients describe an insidious aching pain of the AC region that is exacerbated by weight training, overhead activities, and horizontal adduction. The pain may radiate to the deltoid or trapezium and is relieved by prolonged rest. Frequently, patients report that the pain disturbs their sleep.

In patients who have had protracted symptoms, plain radiographs of the shoulder may reveal subchondral osteolysis. Early in the course, a bone scan may help to confirm AC joint involvement before changes become apparent on plain radiographs.

Avoidance of provocative maneuvers, modification of weight training technique, and ice massage constitute the basis of initial treatment. Since the natural history of this disorder is incompletely understood, the role of corticosteroid injections and surgical intervention (such as distal clavicle excision) is not clear. However, AC joint injections may be effective on a limited basis. If symptoms progress or activity modification is impossible, surgical excision of the distal clavicle may be required. Cahill (7) reports that 37 of 40 patients who had surgical excisions returned to weight training and/or competitive weight lifting.

Spondylolysis.
Spondylolysis is a stress fracture of the pars interarticularis that is presumed to occur from excessive loads on the posterior lumbar spine, usually during lumbar hyperextension. Improper lumbar hyperextension is often seen during squats, military (deltoid) presses, and bench presses. Though data are scarce on the incidence of chronic back pain in weight trainers, it has been shown that 36% of competitive weight lifters have a spondylolytic defect on spine films, compared with 5% of the general population (8). (Spondylolysis has also been associated with gymnastics, wrestling, and the adolescent growth spurt.)

Generally, patients who have spondylolysis present with chronic unilateral low-grade back pain with exacerbations and radiation to the ipsilateral sacroiliac joint. Lumbar extension and hyperextension usually produce the pain.

On physical examination, patients frequently have tight hamstrings, and the stork test is positive (8). To perform the test, the patient balances on the leg that is on the same side as the lumbar pain, then hyperextends the lumbar spine and rotates the trunk toward the symptomatic side. The test, which unilaterally loads the posterior elements, is positive if the maneuver reproduces the patient's pain. The "Scottie dog" sign on oblique lumbar spine radiographs can confirm the diagnosis, and both the oblique and lateral views can also exclude or confirm spondylolisthesis. Bone scans may detect spondylolysis in acute injuries before it is radiographically apparent. Occasionally, single photon emission computed tomography (SPECT) may be needed to more precisely locate the small area of uptake at the lesion.

The treatment of spondylolysis is controversial. Because these injuries are presumably acute stress fractures, some authors have advocated rigid thoracolumbosacral bracing for all patients who have active lesions on bone scans (9). The intent of bracing is to allow the spondylolytic lesion to heal. Others advocate the avoidance of provocative maneuvers (including weight lifting, lumbar spine extension, and impact-loading exercise), relative rest, and back stabilization exercises (10) that stress flexion rather than extension. Nonunion of a pars defect has not been shown to be a cause of chronic back pain.

Spondylolisthesis.
Spondylolisthesis is the anterior subluxation of one vertebral body relative to another. Brady et al (11) found two individuals with spondylolisthesis out of 29 weight trainers who had lumbosacral spine injuries. Congenital cases are the result of bilateral pars elongation, whereas acquired cases are due to bilateral spondylolysis. Slippage of L-5 on S-1 is most common in isthmic spondylolisthesis and is more common in younger people; slippage of L-4 on L-5 is most common in degenerative spondylolisthesis and in older patients.

About half of patients who have spondylolisthesis are asymptomatic, and the condition is an incidental medical finding. Patients who are symptomatic report lumbar pain that is aggravated by strenuous activity, particularly repetitive flexion-extension or hyperextension of the spine.

The percentage of slippage on x-ray guides the management. Symptomatic patients who have slippage of less than 30% can be initially managed conservatively with restriction of vigorous activity, anti-inflammatory drugs or acetaminophen, stretching exercises, and strengthening. Bracing may be helpful for significant muscle spasm, for pain that is unabated despite activity modification, or to allow an acute lysis of the pars interarticularis to heal. In growing adolescents, regular x-ray follow-up is important, and individuals who have rapidly progressing anterior displacement or signs of neurologic compromise should be evaluated for surgical stabilization.

Osteoarthritis.
The prevalence of patellofemoral or tibiofemoral osteoarthritis in former competitive weight lifters has been reported as 31%, vs 14% in competitive runners (10). The same authors also found that patellofemoral arthritis was more prevalent (28%) in weight lifters than in soccer players, runners, and shooters. Suboptimal technique is likely a significant contributing factor for osteoarthritis; for example, squats performed with heavy loads and in which the thighs descend below parallel to the floor place significant load on the thinnest part of the femoral articular cartilage. Repetitive shear force likely takes its toll on the cartilage.

Diagnosis can be made by identifying joint-line tenderness and x-ray evidence of narrowed compartments, tibial plateau ridging, and bony hypertrophy. Standing posteroanterior x-rays in 30° to 45° of flexion are more sensitive in detecting joint space narrowing and osteoarthritic changes. Treatment can include modalities (eg, heat, ice), isolated strengthening and kinetic chain lower-extremity strengthening, orthotic wedges to unload the involved compartment, and activity modification with an emphasis on low-impact to nonimpact aerobic conditioning.

Stress fractures.
Typically, stress fractures occur in the lower extremity from repetitive excessive impact loading activities such as running. The demands placed on the upper extremities during weight training may cause similar overload-induced stress fractures. Stress fractures of the ulna (12), humerus (13), sternum (14), and lumbar ring apophysis (15) have been associated with weight training. Patients generally present with chronic, progressive symptoms. As in lower-extremity stress fractures, management involves the restriction of activity for 6 to 8 weeks.

Physical exam findings in stress fractures can include focal or point tenderness and exacerbation of local pain with a vibrating tuning fork placed on the same bone but distant from the site of tenderness. Early x-rays may be negative; later films may reveal subperiosteal elevation ("bumps") or sclerotic margins. A bone scan may be positive before x-ray changes are evident, showing a focal area of increased uptake.

Other chronic bone injuries that have been associated with weight training include olecranon physeal nonunion (16) and bilateral osteochondral flaps in the wrist (17).

(continued)

[Manfred_Man]

Neuropathies

Acute nerve injuries can occur during weight training, but most neuropathies associated with the activity develop over weeks to months from repetitive traction or focal compression. The most common neuropathies associated with weight training include thoracic outlet syndrome, suprascapular neuropathy, scapular winging, musculocutaneous neuropathy, and notalgia paresthetica. Other conditions that have been reported in the literature include ulnar neuritis (18) and lateral plantar nerve entrapment (19).

Thoracic outlet syndrome.
There have been no reports of specific sports that cause thoracic outlet syndrome (TOS); however, any upper-limb activity can cause symptoms. Because there is no diagnostic "gold standard," the diagnosis and treatment of TOS are controversial. Some authors claim it is rare and largely overdiagnosed, while others claim it is common and underrecognized (20,21).

The subclavian vessels and the brachial plexus pass through several anatomic spaces at the thoracic outlet. In weight lifters, hypertrophy of the scalene muscles can impinge the subclavian vessels and the brachial plexus in the scalene or costoclavicular triangles. Pectoralis minor hypertrophy may impinge the same nerves and vessels in the pectoralis minor space during hyperabduction and external rotation of the shoulder. TOS can be neurogenic and/or vascular.

TOS should be considered whenever a patient reports vague upper-extremity symptoms. In "classic" neurogenic TOS, patients describe insidious upper-limb pain, ulnar hand paresthesias, and thenar weakness consistent with a lower trunk plexopathy. In the majority of patients who have suspected TOS, the history includes pain, nonspecific numbness in the hands, and subjective weakness. The objective physical examination, electromyography (EMG), and vascular studies are usually normal.

Provocative physical examination tests are used to detect TOS, but their specificity is rather low (22,23). One such test is the Roos hyperabduction/external rotation test, in which the patient opens and closes his or her hands for 1 to 3 minutes with elbows bent and arms abducted to 90° and externally rotated (24). The test is positive if the maneuver reproduces the patient's symptoms. But, again, the specificity of this test is low.

To confirm or rule out arterial compression, the physician should examine the supraclavicular or infraclavicular fossa for a mass or bruit, palpate all distal pulses, and take blood pressure measurements of both arms. Laterally rotating the patient's head and extending it backward may increase the accuracy of tests for arterial compression, as can asking the patient to perform Valsalva's maneuver. EMG can be diagnostic if performed proximal to the areas of compression.

For symptomatic patients who test positive for the provocative maneuvers and for those in whom no definitive abnormality can be identified--and TOS is still suspected--management should focus on muscle strength balance between the anterior and posterior thorax, stretching of the pectoral muscles and the anterior shoulder, and patient education about avoiding provocative positions.

Suprascapular neuropathy.
The suprascapular notch, under the transverse scapular ligament, is the most common site for impingement of the suprascapular nerve (figure 6: not shown). Compression of this nerve affects both the supraspinatus and infraspinatus muscles. At this level, the nerve can be traumatized by repetitive shoulder abduction, as in the military press (25,26).

Patients typically present with gradually increasing pain with or without weakness. The weakness may not be apparent to the patient until late in the course when atrophy is noticeable.

The clinical distinction between atrophy from rotator cuff injury and atrophy from suprascapular neuropathy can be difficult, but examining the muscles involved and assessing the degree of atrophy may help differentiate the conditions. Atrophy involving only the supraspinatus muscle could be seen with a supraspinatus tear, but would be unusual for suprascapular neuropathy, which can lead to atrophy in both the supraspinatus and infraspinatus muscles. Isolated infraspinatus atrophy would be unusual for a rotator cuff injury, but could suggest compression of the infraspinatus branch of the suprascapular nerve at the spinoglenoid notch, perhaps from a ganglion cyst.

Nerve conduction studies of the suprascapular nerve and needle EMG can assist with the diagnosis. Magnetic resonance imaging of the shoulder can confirm the integrity of the rotator cuff tendons and can rule out a neuroma in the suprascapular notch (27).

Treatment involves pain medication, gentle assisted range-of-motion exercises to avoid contracture, and strengthening exercises for surrounding muscles--the rhomboids, latissimus dorsi, trapezius, serratus anterior, and especially the scapular stabilizers. Patients can gradually strengthen the affected muscles when pain is gone and the muscle can be moved against some resistance. An EMG may be helpful to document evidence of reinnervation; if the condition is present, strength training can gradually be initiated in a controlled manner. If nonoperative treatment fails, surgery may be needed.

Scapular winging.
Scapular winging is caused by weakness of the serratus anterior muscle from a long thoracic nerve injury, or by weakness of the trapezius muscle from an accessory nerve injury (cranial nerve XI). The injury mechanism is not clear; in many cases, these injuries are idiopathic. No specific exercise has been found to predispose patients to scapular winging, but perhaps the pads on some machines that rest on the shoulders (ie, calf raises, leg presses) could contribute to injury.

Scapular winging from long thoracic nerve palsy is typically more prominent at the inferior medial border of the scapula with shoulder flexion, whereas accessory nerve palsies cause superior medial scapular winging (28).

The diagnosis should include laboratory tests to screen for infectious and inflammatory causes, as well as EMG and nerve conduction studies to establish the level of injury. Treatment consists of relative rest and close follow-up--scapular winging often resolves spontaneously within 3 to 24 months.

Musculocutaneous neuropathies.
In a report (29) of three patients who had musculocutaneous neuropathies, all occurred in the patients' dominant arm and spared the coracobrachialis muscle. The patients' symptoms were precipitated by repetitive biceps curls. Symptoms included biceps muscle pain and weakness. Theoretically, symptoms are caused by impingement of the musculocutaneous nerve from coracobrachialis muscle hypertrophy. Because the symptoms of C-5 or C-6 cervical radiculopathy, brachial plexopathy, and biceps muscle rupture are similar, EMG may be required to establish the diagnosis.

Management is nonoperative, consisting of activity restriction. The three patients described above regained biceps and brachialis muscle function within 3 months (29).

Notalgia paresthetica.
Notalgia paresthetica is thought to be caused by a lesion of a thoracic dorsal primary ramus. It's not known if this condition is seen in weight trainers; the injury mechanism is essentially unknown. Patients typically report chronic pain and sensory symptoms that are frequently described as intense itching in an area 4 to 10 cm in diameter over the thoracic paraspinal muscles at the inferomedial scapula.

Capsaicin can help alleviate symptoms (30). It acts by depleting the local C fiber store of neuropeptides, which are the principal substance responsible for transmitting pain and itching.


Chronic Medical Conditions

Vascular stenosis.
Though uncommon, vascular stenoses may result from repetitive trauma to a blood vessel. Several cases of external iliac artery stenosis in the region of the inguinal ligament have been reported in bicyclists (31). Khaira et al (32) reported on a young bodybuilder who had a similar injury. They hypothesized that the injury resulted from repetitive hip flexion during leg press and squat exercises. Symptoms may include anterior thigh pain. The diagnosis may require vascular studies; treatment in bicyclists has involved vessel grafting.

Weight lifter's cephalgia.
Weight lifters headache is generally sudden in onset and occurs during active lifting (33-35). In many cases, the weight training exercise being performed at the time of headache onset was the bench press. The pain is described as burning or boring in quality and localized to the posterior head and neck. Though onset is abrupt, the headache may persist for several days to weeks, gradually resolving. No clear cause has been identified; the presumed mechanism is ligament or soft-tissue injury.

Initial management consists of avoidance of weight training, cervical range-of-motion exercises and stretches, and pain medication. After a patient's pain resolves, training technique should be reviewed to eliminate incorrect technique.

Weight lifter's heart.
Physiologic stress on the cardiovascular system during weight training changes the myocardial architecture in "weight lifter's heart (36)." The intraventricular septum thickens relative to the ventricular free wall (37). The condition may be inaccurately diagnosed as hypertrophic obstructive cardiomyopathy (HOCM); however, the ratios of intraventicular septum thickness to body surface area and of ventricular free wall thickness to body surface area are the same in weight trainers and controls (37). In patients who have HOCM, these ratios are significantly greater than in controls.

Hernias.
Though hernias are commonly mentioned in association with weight training, and popular weight lifting magazines have many advertisements for hernia repairs, no incidence or prevalence studies have been completed.


Know What to Expect

Becoming aware of the host of chronic conditions that can arise during weight training will help physicians make more efficient use of the time they spend with the next weight trainer who walks through the door with, for example, vague upper-extremity symptoms or a sore shoulder. Questioning patients about their weight lifting practices and making them aware of incorrect technique can help them get back to their fitness routines faster and enable them to work out pain free.

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Dr Reeves is chief resident, Dr Laskowski is a consultant, and Dr Smith is a senior associate consultant in the department of physical medicine and rehabilitation at the Mayo Clinic in Rochester, Minnesota. Dr Laskowski is codirector and Dr Smith is a staff physician at the Mayo Sports Medicine Center, and Dr Laskowski is an associate professor and Dr Smith is an assistant professor at Mayo Medical School in Rochester. Address correspondence to Edward R. Laskowski, MD, Mayo Sports Medicine Center, 200 First St SW, Rochester, MN 55905; e-mail to laskowski.edward@mayo.edu.