The American Journal of Sports Medicine

Postoperative loss of knee motion is a well-recognized phenomenon. This paper reports our results with open debridement and soft tissue release as a salvage procedure in the treatment of patients with severe arthrofibrosis on whom arthroscopic surgical techniques had failed. Eight knees (eight patients) were identified retrospectively. There were four men and four women; mean age was 29 years. All had severely restricted motion with extensive intraarticular and periarticular fibrosis. Range of motion averaged 62.5° preoperatively (flexion 81°, loss of extension 18.8°). Patients underwent open debridement and soft tissue release to restore motion. There were no complications. Motion improved to an average of 124° after surgery. Average flexion improved from 81° to 125°. Loss of extension improved from 18.8° to 1.25°. Functional outcome was good, with Lysholm II scores averaging 79. Patient satisfaction was high. There was a high incidence of patellofemoral arthritis at follow-up. Furthermore, the patellar tendon shortened approximately 6 mm over time. While we do not advocate open debridement and soft tissue release as a first-line treatment for arthrofibrosis, we do conclude that it can be effective as a salvage procedure to restore motion in the profoundly arthrofibrotic knee.

Arthroscopically guided reconstruction of the anterior cruciate ligament is a common orthopaedic procedure. While many associated complications have been described in the literature, postoperative septic arthritis has received little attention. Although rare after anterior cruciate ligament reconstruction, septic arthritis can have devastating consequences. From a group of 831 consecutive patients, we report 4 (0.48%) who sustained septic arthritis. All patients had similar symptoms and were treated by the same surgeon in the same manner. All underwent immediate arthroscopic lavage, open incision, drainage of associated wounds, debridement with graft retention, and treatment with intravenous and then oral antibiotics. The patients underwent an average of 2.75 procedures after the diagnosis to eradicate the infection and restore knee motion. All patients were evaluated at an average of 3 years after surgery. We found that previous knee surgery and meniscal repair were risk factors for the development of postoperative septic arthritis. The infection was successfully eradicated, the ligament graft was preserved, and knee stability and mobility were adequately restored in all patients. However, the clinical outcome of these patients appeared to be inferior to that of patients who had undergone uncomplicated anterior cruciate ligament reconstruction. This inferior outcome appeared to be secondary to damage to the articular cartilage from the infection.

We evaluated the difficulty, accuracy, and safety of establishing a low anterior 5-o'clock portal for anterior capsulolabral repair in patients positioned in the beach-chair position during shoulder arthroscopy. An initial 5-o'clock portal was created using an inside-out technique as described by Davidson and Tibone. During establishment of the portal, significant force was required to lever the humeral head laterally, and chondral indentations were noted in several specimens. Because of the difficulty noted establishing the 5-o'clock portal using an inside-out technique, we attempted to establish a 5-o'clock anterior portal using an outside-in technique. Seven fresh-frozen cadaveric shoulders underwent shoulder arthroscopy in the beach-chair position. After the establishment of a 3-o'clock portal, a specially constructed guide was used to place a pin at the 5-o'clock position. The distances of the pins from the cephalic vein and the musculocutaneous and axillary nerves were recorded. The bottom (5-o'clock position) and top (3-o'clock position) pins varied from 12 to 20 mm from the musculocutaneous and axillary nerves. The bottom pin was located within 2 mm of the cephalic vein and varied from medial to lateral in different specimens. We do not recommend the use of a 5-o'clock portal using an inside-out or outside-in technique for patients positioned in the beach-chair position during shoulder arthroscopy because of the potential for cephalic vein or articular cartilage injury.

The three-in-one procedure for extensor mechanism realignment of the knee combines lateral release, vastus medialis obliquus muscle advancement, and transfer of the medial one-third of the patellar tendon to the tibial collateral ligament. We observed 37 patients (42 knees) receiving this treatment at a minimum 25-month follow-up (range, 25 to 85 months; mean, 44). Thirty-two of 42 knees (76%) with recurrent patellar dislocation had good or excellent results after surgery. Redislocation occurred in four knees (9.5%). Skeletal immaturity, chondral damage, and generalized ligament laxity did not seem to affect outcome. Thirty patients (37 knees) were studied 2 years earlier as well (mean follow-up, 29 months). When comparing the results 2 years later, there was a significant deterioration in outcome over time. These results are comparable with the published results for other techniques of patellar stabilization. We describe the place of the three-in-one operation in our surgical protocol for patellofemoral instability, which is based on the principle that a procedure should be selected to address the underlying pathologic features in an individual case rather than always using one operation for all cases.

This is a prospective study of 431 patients (862 knees) with patellofemoral pain, patellar dislocation, or other abnormalities of the knee joint. There were 217 asymptomatic knees with no contralateral problems for comparison. All patients had a history and physical and radiographic examination of both knees. The radiographs included standard anteroposterior views, axial views at 30° of knee flexion, and standing lateral views at 0° and 30° of flexion. The presence of patellar tilt or subluxation was noted on the axial view. The lateral view of the patella, with precise overlap of the posterior femoral condyles, allowed determination of relationships between the patella's medial edge, median ridge, and lateral edge to assess patellar tilt. Sixty-two percent of patients with patellar dislocations demonstrated subluxation on the axial view, while 98% demonstrated an abnormal lateral view. Eighteen percent of the control knees revealed evidence of subluxation on the axial view while 35% demonstrated subluxation on the extended lateral view. The axial view demonstrated 62% sensitivity for dislocation, while the lateral view taken in full extension demonstrated 98% sensitivity. The specificity for previous dislocation was 82% for the axial view and 93% for the lateral flexed view. Given the high sensitivity of the lateral view for detecting prior patellar dislocation, a normal result on this view can virtually eliminate the question of previous dislocation. Also, with the high specificity of the axial view and lateral view with knee flexion, the two views combined can confirm a clinical impression of patellofemoral malalignment.

The purpose of this prospective study was to determine whether an association exists between foot structure and the development of musculoskeletal overuse injuries. The study group was a well-defined cohort of 449 trainees at the Naval Special Warfare Training Center in Coronado, California. Before beginning training, measurements were made of ankle motion, subtalar motion, and the static (standing) and dynamic (walking) characteristics of the foot arch. The subjects were tracked prospectively for injuries throughout training. We identified risk factors that predispose people to lower extremity overuse injuries. These risk factors include dynamic pes planus, pes cavus, restricted ankle dorsiflexion, and increased hindfoot inversion, all of which are subject to intervention and possible correction.

We examined whether passive stiffness of an eccentrically exercising muscle group affects the subsequent symptoms of muscle damage. Passive hamstring muscle stiffness was measured during an instrumented straight-leg-raise stretch in 20 subjects (11 men and 9 women) who were subsequently classified as “stiff” (N 7), “normal” (N 6), or “compliant” (N 7). Passive stiffness was 78% higher in the stiff subjects (36.2 3.3 N m rad 1) compared with the compliant subjects (20.3 1.8 N m rad 1). Subjects then performed six sets of 10 isokinetic (2.6 rad s 1) submaximal (60% maximal voluntary contraction) eccentric actions of the hamstring muscle group. Symptoms of muscle damage were documented by changes in isometric hamstring muscle strength, pain, muscle tenderness, and creatine kinase activity on the following 3 days. Strength loss, pain, muscle tenderness, and creatine kinase activity were significantly greater in the stiff compared with the compliant subjects on the days after eccentric exercise. Greater symptoms of muscle damage in subjects with stiffer hamstring muscles are consistent with the sarcomere strain theory of muscle damage. The present study provides experimental evidence of an association between flexibility and muscle injury. Muscle stiffness and its clinical correlate, static flexibility, are risk factors for more severe symptoms of muscle damage after eccentric exercise.

To determine whether intermittent exposures to hyperbaric oxygen enhance recovery from delayed-onset muscle soreness of the quadriceps, we conducted a randomized, controlled, double-blinded, prospective study using 66 untrained men between the ages of 18 and 35 years. After the induction of muscle soreness, these subjects were treated in a hyperbaric chamber over a 5-day period in two phases, with four groups (control, hyperbaric oxygen treatment, delayed treatment, and sham treatment) in the first phase; and three groups (3 days of treatment, 5 days of treatment, and sham treatment) in the second phase. The hyperbaric exposures involved 100% oxygen for 1 hour per day at 2.0 atm. The sham treatments involved 21% oxygen for 1 hour per day at 1.2 atm. We monitored recovery using a leg dynamometer to test eccentric torque of the nondominant quadriceps muscle before and immediately after exercise and at 48 and 96 hours after exercise. Pain was tested daily using visual analog pain scales. In phase 1 a significant difference in recovery of eccentric torque was noted in the treatment group compared with the other groups. In phase 2, the recovery of eccentric torque for the 5-day treatment group was significantly greater than for the sham group from immediately after exercise to 96 hours after exercise. The pain data did not differ significantly in any comparison in either phase. The results suggest that treatment with hyperbaric oxygen may enhance recovery of eccentric torque of the quadriceps muscle from delayed-onset muscle soreness.

To evaluate the risks of skiing after anterior cruciate ligament injury with or without reconstruction, we performed a 3-year study of 5646 skiers employed by a large ski resort. All skiers underwent knee ligament examinations before entering the study. The participants were divided into three groups based on whether they had never had an anterior cruciate ligament injury (N 4748), were unilaterally deficient of the ligament (N 138), or had undergone a unilateral reconstruction of the ligament at least 1 year before (N 274). The rates of knee injuries requiring evaluation by a physician or time off work were calculated. The results of the reconstructed knees were further evaluated to determine whether ligament repair with semitendinosus/gracilis or patellar tendon autograft had a higher injury rate. Compared with knees with intact anterior cruciate ligaments, ligament-deficient knees had a 6.2-times higher rate of injuries, and knees in which the ligament had been reconstructed had a 3.1-times higher rate. The differences between each of the three groups were significant. Injuries to ligament-intact knees were less severe, with 13% requiring surgery, while 39% of the injuries in the ligament-deficient and 41% of the injuries in the reconstructed-ligament knees required surgery. The rates of injury for the graft types were not significantly different, but skiers with a semitendinosus/gracilis tendon autograft were significantly more likely to rupture their graft than skiers with a patellar tendon autograft.

Twenty-one knees with acutely injured anterior cruciate ligaments were reconstructed with patellar tendon autografts. Eight of the knees had concomitant medial ligament injuries that were not addressed surgically. Follow-up evaluation (average, 25 months) included computed tomography measurements to analyze transverse-plane laxity in both translation and rotation. These measurements were performed with the patient's leg in a load cell device that stabilizes the distal femur and applies known anterior translational force to the proximal tibia at approximately 20° of flexion. A torque apparatus was used to apply internal and external rotational torque to the leg. Images of the tibial plateau in neutral, internal, and external rotation were performed, with and without an anterior translational force. Both knees of each patient were tested and categorized as group I (anterior cruciate ligament-reconstructed) or group II (uninjured). Translation as measured by computed tomography averaged 1 mm side-to-side difference. Internal rotation averaged 8.7° in group I knees and 10.8° in group II knees. External rotation averaged 9.1° in group I knees and 7.4° in group II knees. The eight knees with concomitant medial ligament injuries were analyzed separately; external rotation without anterior load in group I was 9.5°, compared with 5° in group II. This difference was significant (P 0.01).

Autologous chondrocyte transplantation is a new procedure developed for the treatment of focal articular cartilage defects of the knee. The exact indications and limitations of this procedure have not yet been completely defined through prospective, randomized studies. The purpose of this study was to examine the indications and contraindications for surgery in consecutive cases initially rejected for reimbursement of surgical expenses by insurance companies, but now on appeal, to assess whether patients referred by the physicians met the procedure criteria. Twenty-four consecutive candidates were referred for adjudication when the recommending orthopaedic surgeon appealed a rejection by a medical reviewer. The factors examined included the number and size of the cartilage lesions, the presence of tricompartmental arthritis, transplantation proposed for patellar lesions, patient age, and sagittal plane deformity. In 23 of 24 cases (96%) the indications for the procedure were not met or specific contraindications were present. In 15 of 24 cases (63%) there were multiple contraindications. The results of this study underscore the importance of controlled, application-limited experience before the release of new procedures for widespread clinical applications. The uncontrolled use of this procedure may negatively skew the overall results for this technique, prejudicing a procedure that may be successful for the correct indications.

This study examined four devices for anchorage of hamstring tendons used as anterior cruciate ligament grafts: a stirrup, a clawed washer and screw, and “soft” and round-headed interference screws. Ultimate strength tests were performed using bovine tendons and bones. The stirrup was significantly stronger than the other anchorage devices, failing at 898 N. The clawed washer failed at 502 N, the soft screw at 691 N, and the round-headed screw at 445 N. Cyclic loading to 150 N (to simulate walking) caused elongation of 2.1 mm with the stirrup by 1100 cycles, and 6.7 mm with the clawed washer by 300 cycles. Different hole and soft screw diameters and placements (inside-out versus outside-in) allowed 1- to 3-mm slippage (no significant differences) by 1100 cycles. The round-headed screw allowed 6.8-mm slippage by 1100 cycles, and a sharp edge below the screw head caused tendon damage. Cyclic loads to 450 N (to simulate jogging) were then imposed until failure, and all specimens failed rapidly; only stirrup fixation kept all specimens intact after 300 load cycles. We concluded that anterior cruciate ligament reconstructions using hamstring tendons will slacken if rehabilitation is too aggressive, so forces on the reconstructed ligament should be minimized until tendon-to-bone healing occurs.

We tested pull-out strength and linear stiffness of meniscal repair using bioabsorbable arrows and vertical and horizontal loop sutures in fresh-frozen bovine lateral menisci. In phase I, menisci repaired either with 2—0 Ti-Cron vertical or horizontal loop suture, or 10-, 13-, or 16-mm Meniscus Arrows were loaded to failure at 12.5 mm/sec. In phase II, we examined the number of barbs engaged and angle of insertion using 10- and 13-mm arrows. Pull-out strengths of both suture repair groups were significantly higher than those of the arrow groups. Vertical loop sutures were significantly stiffer than horizontal sutures and 10-mm arrows. In phase II, the mean ultimate load to failure for the 10-mm arrows was 35.1 N, significantly stronger than in phase I (18.5 N); however, stiffness remained low (7.9 N/mm). Five arrows in the 13-mm group were inserted parallel to the tibial surface and showed no significant difference from phase I. Five arrows were inserted at more than a 30° angle. This group was significantly weaker than in phase I. Single vertical loop suture showed the highest overall pull-out strength. Although weaker than sutures, arrows should provide sufficient stability for meniscal healing. The number of barbs engaged and angle of insertion are critical.

Using a cadaveric model, we evaluated the effect of knee and ankle position on the displacement of the severed ends of an Achilles tendon transected at three different points. In six cadaveric legs the Achilles tendon was severed transversely, then marked with radiopaque wire suture. The distance between the wire markers was measured on radiographs taken in different positions of ankle and knee flexion. Ankle plantar flexion had a statistically significant effect on decreasing the gap between the severed ends of the Achilles tendon. This effect was clinically significant as, on average, the tendon edges were separated more than 20 mm when the ankle was in the neutral position and were apposed when the ankle was in 60° of plantar flexion. With the ankle fixed in 60° of plantar flexion, knee position had no significant effect on the displacement of the severed ends of the Achilles tendon. Overall, the effect of knee flexion was neither statistically significant nor clinically significant, as the increase in displacement of the severed ends of the Achilles tendon was only 3 mm from 0° to 120° of knee flexion. These results suggest that the nonoperative treatment of Achilles tendon ruptures requires immobilization in maximal ankle plantar flexion, and that immobilization of the knee may not be necessary to achieve tendon-edge apposition.

We determined the effect of cytokines on the proliferation and migration of cells isolated from the inner-third (white-white), middle-third (red-white), and outer-third (red-red) regions of bovine meniscus. Cells from the outer, or peripheral, region of the meniscus exhibited higher DNA synthesis in the presence of 10% serum compared with cells from the inner or central regions. Recombinant human platelet-derived growth factor-AB, hepatocyte growth factor/scatter factor, and bone morphogenic protein-2 stimulated DNA synthesis of all meniscal cells in a dose-dependent manner, with a two- to threefold maximal stimulation at 10 ng/ml. Cell migration was also stimulated by addition of cytokines. Platelet-derived growth factor and hepatocyte growth factor caused an increase in the migration of cells derived from all three zones, while interleukin-1 selectively stimulated the migration of outer-zone meniscal cells. Epidermal growth factor was much less effective and stimulated the migration of cells in the inner and outer zones by 40% to 50%, while bone morphogenic protein-2 and insulin-like growth factor-1 stimulated the migration of meniscal cells from the middle zone by 40% to 50%. The identification of cytokines that stimulate both the growth and migration of meniscal cells may provide new tools for modulation of meniscal healing.

We investigated the relative contribution of four risk factors to the occurrence of injuries among alpine skiers aged 12 years and younger (3 to 12 years old; mean age, 9.43 years). The risk factors selected were deficient binding adjustment, absence of formal training, low skill level, and use of rented equipment. A group of injured skiers (N 41) and a control group of uninjured skiers (N 313) were recruited among young skiers at one major alpine ski center in the Québec City, Canada, area during the 1995 to 1996 season. No significant group differences were found for mean age or sex distribution. The adjusted odds ratios for injury were 7.54 (95% confidence interval [2.57, 22.15]) for skiers in the low level of skill category relative to highly skilled skiers, 7.14 (2.59, 19.87) for skiers who rented their ski equipment compared with skiers who owned their equipment, and 2.11 (1.02, 4.33) for skiers with ill-adjusted bindings compared with skiers with better-adjusted bindings. Only formal training did not meet the 0.05 significance level for entry into the model; this is probably because of methodologic limitations. Implications of these results for the development of a prevention program aimed at young skiers are discussed.

Normative data are useful for assessing isometric shoulder strength in patients with bilateral shoulder abnormalities. The purpose of this study was to develop a normative database for shoulder strength in the clinically relevant positions and movements. Twenty combinations of exertions and postures—including flexion, extension, abduction, adduction, internal rotation, and external rotation—were tested for both the dominant and nondominant sides. Strength was measured isometrically using a modified Cybex II dynamometer. The cross-sectional study design included 120 subjects (60 women and 60 men) ranging in age from 20 to 78 years from southern Minnesota. Tables of normative strength data were constructed. Multivariate analyses were performed to assess the effect of age, sex, and weight on strength. Age was negatively associated with all strength measures, and weight was positively associated with them. Men were stronger than women when controlling for age and weight. Statistically significant differences between dominant and nondominant shoulders were found for only some of the strength measures taken. These normal data will be useful to the clinician, as they permit a standard against which to compare shoulder strength.

A unique biomaterial, porcine small intestinal submucosa, was used to construct grafts for implantation into surgically created medial meniscal defects in dogs. Five dogs received grafts and two were left untreated as controls. All dogs were evaluated at 4, 8, and 12 weeks by means of lameness scoring, force plate analysis, and ultrasonography. Twelve weeks after implantation the dogs were sacrificed and the replacement tissue was evaluated for gross and histologic appearance, amount, glycosaminoglycan content, and type II collagen immunoreactivity. Four weeks after instrumentation, both groups had lameness scores that were significantly higher than preoperative scores, but at the 8- and 12-week evaluations, scores for the grafted dogs were not different from preoperative values. The ultrasonographic appearance of replacement tissue in grafted defects resembled normal meniscus. In the untreated defects, only unorganized tissue was present. In control dogs, replacement tissue resembled fibrous tissue and cartilage erosions were visible on the medial femoral condyles. In four of the five grafted dogs, replacement tissue was grossly indistinguishable from normal meniscus. The amount of tissue in the defect was significantly greater for the grafted dogs. Histologically, replacement tissue in control dogs was composed of vascularized connective tissue with no evidence of chondroid differentiation. Replacement tissue in grafted dogs closely resembled normal meniscal tissue with respect to chondroid differentiation, collagen content, and zonal architecture. Porcine small intestinal submucosa appeared to have beneficial effects on meniscal regeneration.

Six patients with snapping in the knee were evaluated with clinical history, examination, radiographs, and other imaging. All patients were younger than 40 years and none had an arthritic process. Onset was traumatic in three patients, spontaneous in two, and post-surgical in one. The popping was on the direct lateral aspect of the knee. A consistent examination finding was that the popping was more prominent when the knee was loaded with varus stress during passive flexion and extension cycling, and that it was easily palpated midway between the lateral epicondyle and lateral joint line. Four patients were treated nonoperatively and two had operations. Of those treated without surgery, two had spontaneous resolution of the popping, in one the popping persisted, although not symptomatic enough to require surgery, and one had surgery later. In the surgical group, one patient was treated with popliteus tendon release and one with tenodesis of the popliteus tendon to the fibular collateral ligament. Both procedures were curative and neither led to complicating problems. Follow-up information was not available for the patient with late surgery. Snapping of the popliteus tendon should be recognized as a cause of lateral popping in the knee. It is easily confused with more common sources of mechanical symptoms. Awareness will allow accurate diagnosis and treatment, avoiding unnecessary diagnostic arthroscopy.

This is a special report of the findings of the Concussion Workshop, sponsored by the AOSSM in Chicago in December 1997. Here follows a listing of the members of the workshop: Julian Bailes, MD, American Association of Neurological Surgeons; Arthur Boland, MD, AOSSM; Charles Burke III, MD, National Hockey League; Robert Cantu, MD, American College of Sports Medicine; Letha “Etty” Griffin, MD, National Collegiate Athletic Association; David Hovda, PhD, Neuroscientist, UCLA School of Medicine; Mary Lloyd Ireland, MD, American Academy of Orthopaedic Surgeons; James Kelly, MD, American Academy of Neurology; Greg Landry, MD, American Academy of Pediatrics; Mark Lovell, PhD, Neuropsychology Specialist, Henry Ford Health Systems; James Mathews, MD, American College of Emergency Physicians; Michael McCrea, PhD, Neuropsychology Specialist, Waukesha Memorial Hospital; Douglas McKeag, MD, American Medical Society for Sports Medicine; Dennis Miller, ATC, National Athletic Trainers Association; Jeffrey Minkoff, MD, AOSSM; Stephen Papadopoulus, MD, Congress of Neurological Surgeons; Elliott Pellman, MD, National Football League; Richard Quincy, MS, PT, ATC, Sports Physical Therapy, El Pomar Sports Center; Herbert Ross, DO, American Osteopathic Academy of Sports Medicine; Bryan Smith, MD, National Collegiate Athletic Association; and Edward Wojtys, MD, Workshop Chairman, AOSSM.

The views in this report do not necessarily represent the views of the entire group comprising the Concussion Workshop Group.