The American Journal of Sports Medicine

Water skiing is associated with severe injuries to the proximal hamstring muscles. We wanted to define the mechanism of injury, describe the associated patho logic changes, determine the functional limitations of patients, and suggest measures to prevent injury. Twelve patients with water skiing-related hamstring injuries were included. Six patients were experienced skiers and six were novices. The mechanism of injury was identical in five of six novice skiers. Each sus tained the injury while attempting to get up on one or two skis from a submerged position. In contrast, the expert skiers all sustained injury secondary to a fall while skiing. Physical examination documented evi dence of complete or partial avulsion of the proximal hamstring muscle origins in all patients. In addition, six patients had magnetic resonance imaging or computed tomography scans that confirmed the location and ex tent of the tear. Convalescence ranged from 3 months to 1.5 years before the patient could return to vigorous activities. Seven patients (58%) returned to most of their preinjury sports, albeit at a lower level. Five pa tients (42%), all with complete disruptions, were unable to run or participate in sports requiring agility. Two of these patients required delayed surgical repairs be cause of persistent functional limitations.

We investigated the role of fatigue in muscle strain injuries using the extensor digitorum longus muscles of 48 rabbits. The muscles of the rabbits were fatigued by 25% or 50% then stretched to failure and compared with the contralateral controls. Three rates of stretch were used. The force to muscle failure was reduced in the fatigued leg in all groups (range, 93% to 97.4% compared with the controls). The change in muscle length in the fatigue groups was not different from the controls. The amount of energy absorbed in the fa tigued muscle was 69.7% to 92% that of the energy absorbed in the control muscle. The lowest energy absorption occurred in muscles that were more fa tigued. In eight additional rabbits, fatigued extensor digitorum longus muscles were compared with sub- maximally stimulated muscles with the equivalent con tractile properties, and no difference was seen. Mus cles subjected to strains are frequently injured under high-intensity eccentric loading conditions. Under these conditions, muscles absorb energy and provide control and regulation of limb movement. Our data showed that muscles are injured at the same length, regardless of the effects of fatigue. However, fatigued muscles are able to absorb less energy before reach ing the degree of stretch that causes injuries.

We compared open and arthroscopic stabilizations of true Bankart lesions in patients with traumatic, unidi rectional anterior glenohumeral dislocations. The 27 patients were men (age range, 18 to 56 years) who were involved in recreational sports. One group (15 patients) had elected an arthroscopic Bankart repair; the other group (12 patients) had chosen open stabili zation with a standard deltopectoral approach. Patients were followed up 17 to 42 months after surgery by examination, radiographs, and interviews. In the open repair group, 1 of the 12 patients experienced a sub luxation in the follow-up period, but no patients had dislocations or reoperations. In the arthroscopic group, 5 of 15 patients had experienced subluxation or dislo cation ; of these 5 patients, 2 underwent reoperation. The arthroscopic group had significantly worse results in satisfaction, stability, apprehension, and loss of for ward flexion in the operated limb. In summary, the arthroscopic procedure did not significantly improve function; instead, it produced an increased failure rate compared with the open procedure. Therefore, we be lieve that open stabilization remains the procedure of choice for patients with true Bankart lesions.

We studied 54 patients with shoulder pain secondary to anterior instability or glenoid labral tears refractory to 6 months of conservative management with no evi dence of rotator cuff lesions. All patients had sufficient preoperative clinical data, magnetic resonance imag ing, and shoulder arthroscopy results for analysis. The ability to predict the presence of a glenoid labral tear by physical examination was compared with that of mag netic resonance imaging (conventional and arthro gram) and confirmed with arthroscopy. There were 37 men and 17 women (average age, 34 years) in the study group. Of this group, 64% were throwing athletes and 61% recalled specific traumatic events. Clinical assessment included history with specific attention to pain with overhead activities, clicking, and instances of shoulder instability. Physical examination included the apprehension, relocation, load and shift, inferior sulcus sign, and crank tests. Shoulder arthroscopy confirmed labral tears in 41 patients (76%). Magnetic resonance imaging produced a sensitivity of 59% and a specificity of 85%. Physical examination yielded a sensitivity of 90% and a specificity of 85%. Physical examination is more accurate in predicting glenoid labral tears than magnetic resonance imaging. In this era of cost con tainment, completing the diagnostic workup in the clinic without expensive ancillary studies allows the patient's care to proceed in the most timely and economic fashion.

A 3-year prospective study was initiated to evaluate torsional resistance of modern football cleat designs and the incidence of surgically documented anterior cruciate ligament tears in high school football players wearing different cleat types. We compared four styles of football shoes and evaluated the incidence of ante rior cruciate ligament tears among 3119 high school football players during the 1989 to 1991 competitive seasons. The four cleat designs were 1) Edge, longer irregular cleats placed at the peripheral margin of the sole with a number of smaller pointed cleats positioned interiorly (number of players wearing this shoe, 2231); 2) Flat, cleats on the forefoot are the same height, shape, and diameter, such as found on the soccer- style shoe (N = 832); 3) Screw-in, seven screw-in cleats of 0.5 inch height and 0.5 inch diameter (N = 46); and 4) Pivot disk, a 10-cm circular edge is on the sole of the forefoot, with one 0.5-inch cleat in the center (N = 10). The results showed that the Edge design produced significantly higher torsional resistance than the other designs (P < 0.05) and was associated with a significantly higher anterior cruciate ligament injury rate (0.017%) than the other three designs combined (0.005%).

We prospectively observed 38 patients with nonopera tively treated isolated partial ruptures of the knee me dial collateral ligament at 3 months, 4 years, and 10 years after the initial trauma using clinical and radio graphic examinations. The initial diagnoses were based on clinical and arthroscopic examinations. Three months after injury, 28 patients (74%) had re gained nearly normal knee function and muscle strength, and 75% of these patients could perform at their preinjury activity level (competitive team sports). Five patients (13%) had increased valgus laxity (grade I) in the injured knee. After 4 years, the patients had a median Lysholm score of 100 (range, 64 to 100). Thir ty-three patients (87%) had normal knee function dur ing strenuous activities. Repeat injuries to the medial collateral ligament occurred in two patients (5%), and another two patients sustained cruciate ligament inju ries during the follow-up period. After 10 years, the Lysholm score (median, 95; range, 73 to 100) was lower compared with the 4-year score (P < 0.03), but the patients still performed on a similarly high activity level. Five patients (13%) had distinct signs of begin ning osteoarthritis (Fairbank's signs) on radiographs, but none had joint space reduction.

We prospectively looked at the diagnostic accuracy of clinical examination of the knee in patients with arthro scopically documented knee injuries. The study in cluded 156 patients with 156 knee injuries (72 acute and 84 chronic) who were seen during 1 year at Martin Army Hospital at Fort Benning Georgia. All patients were given a primary diagnosis based on their history, physical examination, and routine radiographs. Fifty- seven patients were also given one or more secondary diagnoses. Magnetic resonance imaging scans and arthrograms were not used in the evaluation of these patients. The primary diagnosis was correct in 83% of the knees. Of 57 secondary diagnoses given, 54% were correct and 31 % were incomplete. An incorrect diagnosis was made in 14% of knees for both primary and secondary diagnoses. There were four patients with no identifiable lesion other than synovitis. With the increasing cost of medical care, the need for expensive diagnostic studies such as magnetic resonance imag ing needs to be evaluated. The cost of a magnetic resonance image scan ranges between $600 to $1200 depending on the institution. The use of magnetic res onance imaging as a routine diagnostic aid in the clin ical examination of the knee is unnecessary. Arthro scopic surgery of the knee should be based on the patient's history, physical examination, and radio graphs.

The accuracy of magnetic resonance imaging of the hip was prospectively evaluated in 19 military subjects engaged in endurance training. These patients had hip pain, negative radiographs, and radionuclide bone scans consistent with femoral neck stress fracture. Twenty-two hips were identified as positive for femoral neck stress fracture by bone scan. Each patient under went magnetic resonance imaging and 6-week fol low-up plain radiographs of the hips. Magnetic reso nance imaging studies differentiated femoral neck stress fractures from a synovial pit, iliopsoas muscle tear, iliopsoas tendinitis, obturator externus tendinitis, avascular necrosis of the femoral head, and a unicam eral bone cyst. The follow-up radiographs were used to verify the diagnosis of stress fracture. The radiographs showed healing callus in patients with stress fractures. Patients with diagnoses other than stress fractures had no changes on follow-up radiographs. Magnetic reso nance imaging studies were as sensitive and much more specific than bone scan in determining the cause of hip pain. Radionuclide bone scan had an accuracy of 68% for femoral neck stress fractures with 32% false-positive results; MRI was 100% accurate. Mag netic resonance imaging proved to be superior to ra dionuclide bone scanning in providing an early and accurate diagnostic tool that aided in the differential diagnosis of hip pain in the young endurance athlete.

Seven fresh-frozen cadaveric elbows were used to evaluate the extent to which the medial collateral liga ment must be injured before arthroscopic evidence of valgus instability is seen, the amount of ulnohumeral joint opening that does occur after such an injury, and the elbow position that maximizes visualization of this opening. While visualizing the most medial aspect of the ulnohumeral joint arthroscopically through the an terolateral portal, we sequentially sectioned the medial collateral ligament complex until all of the medial liga mentous restraints were cut. A valgus load was applied after each incision, and the extent to which the ulno humeral joint opened was measured. Ulnohumeral joint opening was not visualized in any specimen until complete sectioning of the anterior bundle was per formed. After the anterior bundle was released, 1 or 2 mm of joint opening was present in all specimens. Complete release of the medial collateral ligament led to dramatic increases in medial joint opening in all seven specimens (4 to 10 mm). Varying the angle of elbow flexion from 15° to 120° revealed that visualiza tion of the medial joint opening was best at 60° to 75°. Finally, forearm pronation increased ulnohumeral joint opening and supination decreased joint opening in all specimens. We found that the entire anterior bundle must be sectioned before measurable and reproduc ible medial joint opening can occur.

Our study evaluated the results of surgical repair of acute carpal scaphoid fractures in athletes and the time required for the athletes to return to play. Although playing casts are a nonsurgical option, they reduce the effectiveness of the athlete in sports that require max imal manual dexterity; thus, the management of scaph oid fractures is challenging when early return to sports is desired. Twelve athletes with 12 acute midthird scaphoid fractures were treated with Herbert screw fixation. All patients were in-season athletes in sports that precluded the use of a playing cast. Return to sports averaged 5.8 weeks. Nine of the 12 athletes had range of motion equal to the uninjured side. The grip strength was equal to the unaffected side in 10 of the 12 athletes. Clinical and radiographic union was evi dent in 11 subjects at an average followup of 2.9 years. The healing rates were comparable with other treat ment modalities. We concluded that internal fixation of a scaphoid fracture allows safe and early return to sports when a playing cast is not an acceptable option and when an athlete accepts the risks of surgery.

Weight training is an integral part of most athletic con ditioning programs; yet, the effect of these programs on neuromuscular function remains unclear. To exam ine the neuromuscular effects of training and condition ing at the knee joint, 32 volunteers (16 men and 16 women; average age, 25.4 years) were placed into one of four groups: isokinetic, isotonic, agility, or control. Each group trained 3 days per week for 6 weeks. The knee function of all participants was evaluated just before and after the 6-week training period. The agility- trained group significantly improved the spinal reflex times of the lateral and medial quadriceps muscles in response to anterior tibial translation. The cortical re sponse time of the agility group also significantly im proved in the gastrocnemius, medial hamstring, and the lateral quadriceps muscles. Interestingly, the corti cal response time of the medial hamstring and the medial quadriceps muscles in the isokinetic group slowed significantly, by 39.1 and 32.4 msec, respec tively, after 6 weeks of training. Isotonic and isokinetic strength training of the lower extremities do not appear to improve muscle reaction time to anterior tibial trans lation, whereas agility exercises potentially improve this parameter.

In this prospective, randomized study we assessed the use of cold therapy after arthroscopic anterior cruciate ligament reconstruction. Seventy-one patients were randomly allocated, without the knowledge of the sin gle surgeon, to one of three groups: Group I had an ice water-filled CryoCuff fitted in the operating theater after surgery, Group II had room temperature water in the CryoCuff, and Group III patients had no CryoCuff. Pa tients were well matched for age, sex, and associated surgery. An independent observer measured blood loss, analgesic use, range of motion, and visual analog pain scores postoperatively. There were no differences between any of the three groups regarding the vari ables measured. The use of cold therapy devices as an adjunct to the postoperative management of these pa tients must be questioned.

The MOS 36-item short-form health survey is a ge neric, patient-based health assessment tool. It has been used to assess functional outcome for many medical conditions, both acute and chronic. The use of this survey in evaluating the effects of treatment of any specific disease or injury allows comparison of treat ments across a broad spectrum of disease categories. The purpose of this study was to see if this assessment tool could 1) be used to identify those patients requiring anterior cruciate ligament reconstruction, 2) detect changes in the patients with treatment over time, and 3) correlate with the commonly used knee assessment scales. The short-form health survey could not identify those patients requiring anterior cruciate ligament re constructive surgery. However, it did show important and significant changes with treatment (surgical and nonsurgical) over time. There was a significant corre lation between the short-form health survey and the Lysholm and International Knee Documentation Com mittee scores during this study. The addition of the MOS 36-item short-form health survey to our traditional knee ligament evaluation tools is encouraged. Its use will permit the orthopaedic community to demonstrate the value of our treatment of anterior cruciate ligament injuries to health care planners and generalist physi cians.

We designed a study to determine whether chronic encephalopathy occurs in elite, active soccer players resulting from repetitive heading of the soccer ball. Studies have suggested that the cumulative effects of heading a ball can cause a chronic brain syndrome similar to dementia pugilistica, which is seen in profes sional boxers. Twenty of 25 members of the U.S. Men's National Soccer Team training camp (average age, 24.9; average years of soccer, 17.7), who com pleted a questionnaire on head injury symptoms and had magnetic resonance imaging of the brain, were compared with 20 age-matched male elite track ath letes. The soccer players were surveyed about playing position, teams, number of headers, acute head inju ries, and years of playing experience. An exposure index to headers was developed to assess a dose- response effect of chronic heading. The soccer and track groups were questioned regarding alcohol use and history of acute head traumas. Questionnaire anal ysis and magnetic resonance imaging demonstrated no statistical differences between the two groups. Among the soccer players, symptoms and magnetic resonance imaging findings did not correlate with age, years of play, exposure index results, or number of headers. However, reported head injury symptoms, especially in soccer players, correlated with histories of prior acute head injuries (r = 0.63). These findings suggest that any evidence of encephalopathy in soccer players relates more to acute head injuries received playing soccer than from repetitive heading.

The incidence and distribution of stress fractures were evaluated prospectively over 12 months in 53 female and 58 male competitive track and field athletes (age range, 17 to 26 years). Twenty athletes sustained 26 stress fractures for an overall incidence rate of 21.1%. The incidence was 0.70 for the number of stress frac tures per 1000 hours of training. No differences were observed between male and female rates (P > 0.05). Twenty-six stress fractures composed 20% of the 130 musculoskeletal injuries sustained during the study. Although there was no difference in stress fracture incidence among athletes competing in different events (P > 0.05), sprints, hurdles, and jumps were associated with a significantly greater number of foot fractures; middle- and long-distance running were as sociated with a greater number of long bone and pelvic fractures (P < 0.05). Overall, the most common sites of bone injuries were the tibia with 12 injuries (46%), followed by the navicular with 4 injuries (15%), and the fibula with 3 injuries (12%). The high incidence of stress fractures in our study suggests that risk factors in track and field athletes should be identified.

Three blinded observers on three separate occasions calculated four commonly employed patellar height ra tios on the knees of 15 patients who had three lateral radiographs each. The observers used the same mea surement instrument, a hand-held goniometer ruler, to determine the relative reliability of each patellar height ratio. The measurements by the three observers were examined, and the error and reliability of the four meth ods of measurement were tested statistically. Among the four methods of measuring patellar height that we studied, the Blackburne-Peel method most consis tently reproduced the patellar height index. Interob server measurement error averaged 0.06 for all ratios. Values greater than 0.06 represented real patellar height changes. The ratios were not significantly af fected by the change of knee flexion angle from 30° to 50°. Side-to-side patellar height measurement differ ences averaged 0.16, which suggests that the healthy contralateral limb is not reliable as a control. Mild ar thritic changes decreased variability of measurements by an average of 24% because small osteophytes better defined the articular margins of the patella.

Meniscal transplantation has been suggested as an alternative to total meniscectomy, which is now known to lead to long-term osteoarthritic degeneration of the knee joint. To evaluate the success of meniscal trans plantation, we divided 28 sheep knees into 4 groups: total meniscectomy, allograft, autograft, and control. After a mean postoperative time of 21.4 months, we radiographed the excised knee joints in a loaded state and graded the radiographs for osteoarthritic changes. The knees with meniscectomies, allografts, and au tografts showed significantly more degenerative changes than the control knees. However, there were no statistically significant differences between these three groups. The results of this study suggest that meniscal allograft transplantation does not protect the knee against degenerative changes.

With increasing use and availability of musculoskeletal soft tissue allografts, orthopaedic surgeons need cur rent knowledge about allograft processing, costs, and availability. In conjunction with the American Associa tion of Tissue Banks, a comprehensive survey consist ing of specific questions on several topics in tissue banking was sent to 42 member banks or banks un dergoing accreditation review that distribute musculo skeletal tissues. Donors came from organ procurement organizations, coroners' offices, hospital morgues, and donations; the average age of the donors was 35. Most of the 36 tissue banks responding to the questionnaire harvest patellar and Achilles tendons. Patellar tendon demand exceeded supply. Tissue processing was done by outside organizations approximately 50% of the time. Of the four types of tissue sterilization pro cesses performed, gamma irradiation was the most common. Doses of sterilizing gamma irradiation varied from 1 to 3.5 mrad. The average approximate costs of fresh-frozen tissue were $800 for patellar tendon al lograft, $615 for Achilles tendon, and $640 for menisci. There was no consensus of opinion of how to size or sterilize meniscal allografts. As demand increases for soft tissue allografts, it is essential that the orthopaedic surgeon is knowledgeable about the clinical impact of tissue banking.

Axial compressive loading, the principal cause of spi nal cord quadriplegia in American football, is produced when a player is forcibly struck on the crown of the helmet. This impact subjects the small cervical verte brae to a large compressive force that often produces stress that exceeds the failure limit of the spine. Sev eral factors influence the outcome in axial collisions, including the available kinetic energy, the displace ment needed to dissipate the energy, and the end conditions of the collision (i.e., the position of the head). Effective intervention of this catastrophic injury requires the melding of information from the fields of biomechanics and epidemiology. From a biomechani cal perspective, neck loading should be kept at a level that is below the failure limit of the cervical spine. The epidemiologic rate at which these injuries develop among football players suggests that cervical quadri plegia is rare. Thus, protective devices intended to lower the forces on the cervical spine may not succeed in dramatically reducing the incidence of this injury. Because this injury is rare, it is important to consider that introducing new protective equipment, intended for intervention of one problem (i.e., cervical quadriplegia), may lead to other injuries.

We retrospectively reviewed the office records of the senior author—which include two national ballet com panies—and identified 35 dancers who sustained dis tal shaft fractures of the fifth metatarsal. The usual fracture pattern is a spiral, oblique fracture starting distal-lateral and running proximal-medial. Treatment consisted of open reduction and internal fixation for 2 patients, closed reduction and percutaneus fixation for 2 patients, short leg weightbearing cast for 7 patients, and an elastic wrap and treatment of symptoms for 24 patients. Patients with marked displacement of the fracture underwent internal fixation early in the study period; but more recent treatment emphasized nonop erative means, even for displaced fractures. The aver age time to pain free walking was 6.1 weeks (range, 0 to 16); return to barre exercises, 11.6 weeks (range, 4 to 48); and return to performance, 19 weeks (range, 6 to 52). There was one delayed union (7 months) and one refracture (2 months) that subsequently healed. All patients returned to professional performance without limitation and no patient reported pain with perfor mance at followup. Spiral fractures of the distal shaft of the fifth metatarsal are common injuries and can usu ally be treated nonoperatively for these high perfor mance athletes without long-term functional sequelae.