Medial reefing without lateral release for recurrent patellar instability: midterm and long-term outcomes.

BACKGROUND: There is no consensus on the optimal surgical technique for recurrent patellofemoral instability. Despite many different surgical procedures discussed in the literature, there are few studies with long-term outcomes. HYPOTHESIS/PURPOSE: The purpose of this study was to compare subjective and objective preoperative data from patients with recurrent patellar instability and normal alignment to midterm and long-term outcomes after an arthroscopically assisted medial reefing technique. The hypothesis was that the previously reported successful outcomes at 60 months would be well maintained over time. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: A total of 19 patients (20 knees) with recurrent patellar instability and normal bony anatomy underwent arthroscopically assisted medial reefing without lateral release. They were evaluated preoperatively and then at midterm (average, 63 months) and long-term (average, 142 months) follow-ups. Patients underwent a history assessment, physical examination, and radiographic evaluation. Outcomes evaluated included Lysholm and Tegner scores, subjective data, and examination and radiographic findings. Operative reports were reviewed for the presence of chondral lesions. Comparative statistics were utilized (P < .05). RESULTS: All patients were satisfied with their surgery results and would undergo the procedure again. There was 1 recurrent subluxation and no recurrent dislocations. Subjective symptom scores demonstrated significant improvement from preoperative to midterm and long-term follow-ups for pain, instability, and swelling. Both Lysholm and Tegner scores improved significantly from preoperative to midterm and long-term follow-ups. At long-term follow-up, 70% of the patients reported excellent or good results, 5 patients reported fair results, and 1 patient reported a poor result. However, Tegner activity scores decreased significantly from midterm to long-term follow-ups. Significant improvement from preoperative to midterm and long-term follow-ups was demonstrated in physical examination findings including decreases in patellar apprehension and patellar quadrant glide; however, there was no significant difference in retropatellar pain or range of motion. For radiographic measurements, the lateral patellofemoral angle was significantly improved from preoperative to midterm and long-term follow-ups. At long-term radiographic analysis, 5 knees (25%) had narrowing of the patellofemoral joint space, 10 knees (50%) revealed patellofemoral osteophytes, and 7 knees (35%) demonstrated a medial ossicle. The presence of preoperative chondral lesions resulted in significantly lower Lysholm and Tegner scores and increased findings of osteoarthritis at long-term follow-up. CONCLUSION: Arthroscopically assisted medial reefing, without lateral release, is an effective long-term treatment for patients with recurrent patellar instability and normal bony anatomy.

The effect of medial opening wedge proximal tibial osteotomy on patellofemoral contact.

BACKGROUND: It has been suggested that patellofemoral contact pressures and contact forces may be altered secondary to an opening wedge high tibial osteotomy, yet few data are available that quantify the effect of varying degrees of medial opening wedge osteotomy on the patellofemoral joint contact characteristics. HYPOTHESIS: Opening wedge medial proximal tibial osteotomy will increase patellofemoral contact force and pressure. STUDY DESIGN: Controlled laboratory study. METHODS: Nine human cadaver knees were used. Pressure-sensitive film was placed in the suprapatellar pouch, leaving the patellar tendon and medial and lateral retinacula intact. The quadriceps tendon was attached to a materials testing machine along the axis of the femur, whereby a pulley mechanism generated 950 N of force. Patellofemoral contact characteristics were measured with pressure-sensitive film at 30°, 60°, 90°, and 120° of flexion for the native knee and after subsequent 10-mm and 15-mm medial opening wedge proximal tibial osteotomies. The film was analyzed with imaging software. RESULTS: There was a statistically significant increase (P < .05) in mean contact pressure at 30° and 120° between the 10-mm osteotomy and native knee and across all flexion angles between the 15-mm osteotomy and native knee. Furthermore, a significant difference was seen in peak pressures when native knees were compared with 10-mm and 15-mm opening wedge osteotomies at all flexion angles. CONCLUSION: There was a significant increase in patellofemoral pressures at varying degrees of knee flexion after medial opening wedge proximal tibial osteotomies of only 10 mm; a larger osteotomy resulted in a greater increase. CLINICAL RELEVANCE: When performing a medial opening wedge proximal tibial osteotomy, the surgeon should consider the negative effects of increased patellofemoral peak pressure.

A prospective randomized study comparing a forearm strap brace versus a wrist splint for the treatment of lateral epicondylitis.

BACKGROUND: The outcome is unknown for 2 common bracing treatments utilized for patients with lateral epicondylitis. The purpose of this study was to compare the clinical outcomes of a wrist splint with that of a counterforce forearm strap for the management of acute lateral epicondylitis. MATERIALS AND METHODS: Forty-two patients (44 elbows) received either a wrist extension splint (Group I-24 elbows) or a counterforce forearm strap (Group II-20 elbows). Measures on the Mayo Elbow Performance (MEP) and American Shoulder and Elbow Society (ASES) Elbow Assessment Form were collected prior to treatment and at 6 weeks. A total score was derived, utilizing the ASES Elbow Assessment, as was a score utilizing the standard scoring system for the MEP. RESULTS: Group I's score derived from the ASES form improved 16 points and Group II's score improved 13 points. Group I's score on the MEP improved 13 points and Group II's score improved 12 points. There was no significant difference measured between the Groups with the ASES (P = .60) nor MEP (P = .63) scores. However, within the ASES derived score, pain relief was significantly better with the extension splint group (P = .027). No other variables were statistically significantly different. DISCUSSION: Significant pain relief with the wrist extension splint may be due to improved immobilization of the wrist extensor muscles in a resting position. CONCLUSION: The wrist extension splint allows a greater degree of pain relief than does the forearm strap brace for patients with lateral epicondylitis.

Relative contribution of acromioclavicular joint capsule and coracoclavicular ligaments to acromioclavicular stability.

HYPOTHESIS: We hypothesized that both the AC joint capsule and CC ligaments are biomechanically robust structures in the anterior-posterior (AP) and superior-inferior (SI) planes with low loads, and that these ligaments provide essential function in AC joint stability. MATERIALS AND METHODS: Anterior-posterior (AP) and superior-inferior (SI) AC joint translations were quantified in 6 cadaver matched pairs with AC joint compressions of 10N, 20N and 30N, and with translational loads of 10N and 15N. Either the AC joint capsule or CC ligaments were transected, and measurements were then repeated. Biomechanical characteristics of the remaining AC joint capsule or CC ligaments were compared. RESULTS: There were significant increases in AP translation with the cut AC joint capsule, and significant increases in SI translation with the cut CC ligaments (P < 0.0001). Compression significantly decreased translation (P < 0.0001). DISCUSSION: Our study is supported by, and further develops, recent studies and anatomical knowledge. It offers two interpreted pieces of information for the sports medicine physician to consider for reconstruction of the AC joint. First, resection of the distal clavicle may have a detrimental effect. Second, repair of the AC joint capsule, in addition to the customarily repaired CC ligaments, appears to have a beneficial effect. CONCLUSION: The AC joint capsule is a robust anatomical structure that contributes significantly to the AC joint stability, especially in the AP plane. Compression increases stability. LEVEL OF EVIDENCE: Basic science study.

Comparison of preseason, midseason, and postseason neurocognitive scores in uninjured collegiate football players.

BACKGROUND: College football players sustain an average of 3 subconcussive blows to the head per game. Concussions correlate with decreases in standardized neurocognitive test scores. It is not known whether repetitive, subconcussive microtrauma associated with participation in a full season of collision sport affects neurocognitive test scores. HYPOTHESIS: No difference exists between preseason, midseason, and postseason Standardized Assessment of Concussion (SAC) and Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT) scores when collegiate football players sustain subconcussive microtrauma from forceful, repetitive contact activity. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Fifty-eight members of a Division III collegiate football team who had no known concussion during the season voluntarily completed the SAC and ImPACT instruments preseason, midseason, and postseason. A repeated measures analysis of variance was used to compare the scores at the 3 time intervals (P < .05). RESULTS: No statistically significant decreases were found in overall SAC or ImPACT scores or in any of the domains or composites of the tests (P < .05) when preseason, midseason, and postseason scores were evaluated. CONCLUSIONS: ImPACT and SAC neurocognitive test scores are not significantly altered by a season of repetitive contact in collegiate football athletes who have not sustained a concussion. CLINICAL RELEVANCE: A diminution in SAC or ImPACT scores in concert with clinical symptoms and findings should be interpreted as evidence of a postconcussive event.

Arthroscopically assisted medial reefing without routine lateral release for patellar instability.

BACKGROUND: Patellofemoral instability in patients with normal alignment has been effectively treated with medial reefing procedures and a lateral release. Recent research suggests that a lateral release may not be necessary in patients without excessive patellar tilt. HYPOTHESIS: Arthroscopically assisted medial reefing without lateral release is as effective as techniques with a lateral release reported in the literature. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Twenty-four patients (25 knees) were observed for an average of 60 months. Preoperatively, patients underwent a history, physical examination, and radiographic evaluation. At follow-up, a physical examination and radiographic evaluation were repeated. Preoperative and postoperative Lysholm and Tegner scores were calculated. A subjective questionnaire was also completed. Comparative statistics were used for the preoperative and postoperative scores (P < .05). RESULTS: Ninety-six percent (24/25) were satisfied with their results, and all patients would have the same procedure performed again. Subjective symptom scores improved significantly. Lysholm knee scores improved from an average of 54 to 91 (P < .001). Tegner activity level improved from an average of 3.3 to 6.2 (P < .001). Significant improvement was seen in patellar mobility, apprehension, and patellofemoral tenderness with compression. Range of motion, muscle atrophy, and tilt did not change significantly. Congruence angles improved from 4.4 degrees to -2.5 degrees (P = .009), lateral patellofemoral angles improved from 5.5 degrees to 8.7 degrees (P = .011), and lateral patellar displacement improved from 2.0 to 0.2 mm (P < .044). There were no recurrent dislocations or subluxations. CONCLUSION: Arthroscopically assisted medial reefing, without lateral release, is an effective treatment for patients with recurrent patellofemoral instability and normal alignment.

Assessment of reprocessed arthroscopic shaver blades.

PURPOSE: The purpose of this study was to evaluate the level of contaminants on, as well as the quality of, reprocessed shaver blades. METHODS: We assessed 7 new shaver blades and 27 shaver blades that had been reprocessed with mechanical cleaning, functional testing, and sterilization with ethylene oxide. A spectrophotometer measured the amount of nucleic acid and protein. The blade quality was assessed by photographing the blades with magnification and determining the percentage of damage present on each blade. A subset of shaver blades were then used to cut meniscal tissue, and the cut surface was measured for smoothness by image processing and automated laser scanning cytometry. In evaluation of the meniscus, for the subset of shavers, an image processing value of 1 indicates a smooth, straight line, and values lower than 1 reflect deviations in the cut surface (the closer the value is to 1, the smoother the surface). Laser scanning cytometry values indicate the percentage of irregularities in the cut surface (the lower the value is, the smoother the surface). RESULTS: Of the 27 reprocessed shaver blades, 13 (48%) had detectable levels of protein and 17 (63%) had detectable levels of nucleic acid. On the reprocessed shaver blades, protein levels ranged from 2.43 microg to 60 microg and nucleic acid levels ranged from 0.40 microg to 3.5 microg. No new shaver blade had contaminants. Twenty reprocessed shaver blades had been manufactured with teeth and could be evaluated for visible damage. Of these, 10 had 1% to 25% damage, 5 had 26% to 50% damage, 3 had 51% to 75% damage, and 2 had 76% to 100% damage. The new blades had no visible damage. Image processing revealed smoothness of the surface cut with new shaver blades, yielding values of 1 +/- 0.12, whereas the values for reprocessed shaver blades ranged from 0.62 +/- 0.02 to 1 +/- 0.07. Laser scanning cytometry values ranged from 3.3% to 7.1% for the new blades as compared with 5.8% to 20.0% for the reprocessed blades. CONCLUSIONS: Of the reprocessed shaver blades, 48% had detectable levels of protein and 63% had detectable levels of nucleic acid. All of the reprocessed blades visually evaluated showed some level of damage or wear, whereas no new blade had such damage. In addition, menisci cut with reprocessed shavers showed rougher edges than did menisci cut with new shavers. CLINICAL RELEVANCE: To make an informed decision regarding the use of reprocessed shaver blades, surgeons will want to know the level of contamination on, and the quality of, reprocessed shaver blades.

The effect of tennis racket grip size on forearm muscle firing patterns.

BACKGROUND: Inappropriately sized tennis racket grip is often cited in the popular media as a risk factor for overuse injuries about the forearm and elbow. Currently, a hand measurement technique developed by Nirschl is commonly used by tennis racket manufacturing companies as the method for determining a player's "recommended" grip size. HYPOTHESIS: Quarter-inch changes from that recommended by Nirschl in tennis racket grip size will have no significant effect on forearm muscle firing patterns. STUDY DESIGN: Controlled laboratory study. METHODS: Sixteen asymptomatic Division I and II collegiate tennis players performed single-handed backhand ground strokes with rackets of 3 different grip sizes (recommended measurement, undersized (1/4) in, and oversized (1/4) in). Fine-wire electromyography was used to measure muscle activity in extensor carpi radialis longus and brevis, extensor digitorum communis, flexor carpi radialis, and pronator teres. Repeated-measure analysis of variance was used for within-group comparisons, comparing different grips in specified phases for backhand ground strokes (P

Biomechanical comparison of traditional and locked suture configurations for arthroscopic repairs of the rotator cuff.

BACKGROUND: The optimal suture configuration for arthroscopic rotator cuff repairs is controversial. "Locked" suture configurations, which use a combination of simple and transverse suture loops, have demonstrated better fixation strength than have traditional simple and horizontal mattress techniques. PURPOSE: To compare traditional arthroscopic suture configurations to locked arthroscopic configurations in ability to resist gap formation under cyclic loading. STUDY DESIGN: Controlled laboratory study. METHODS: Crescent-shaped defects were created at the infraspinatus tendon insertion in 32 bovine shoulders. Four arthroscopic suture configurations were tested (8 specimens in each group): simple (group 1), horizontal mattress (group 2), locked mattress (group 3), and locked inverted mattress (group 4). A metal corkscrew suture anchor doubly loaded with No. 2 Fiberwire suture was used for the repairs. A cyclic loading protocol with application of forces from 10 to 180 N for a maximum of 2,500 cycles was used. The number of cycles required to form gaps of 5 mm and 10 mm was recorded. RESULTS: The locked mattress configuration (group 3) outperformed all other groups in resisting 5-mm gap formation (P < .0001), requiring a mean of 628 cycles in comparison to 65, 193, and 197 cycles for groups 1, 2, and 4, respectively. Both locked configurations (groups 3 and 4) were superior to traditional simple and horizontal mattress configurations in resisting 10-mm gap formation. CONCLUSION: The locked mattress suturing technique (group 3) provided the most secure tendon fixation of all arthroscopic configurations tested. CLINICAL RELEVANCE: The use of locked suture configurations for arthroscopic rotator cuff repairs may enhance tendon fixation and limit gap formation in the early postoperative period.

In vitro effects of 3 common arthroscopic instruments on articular cartilage.

PURPOSE: The purpose of this study was to compare chondroplasty performed with an ExoJet high-pressure fluid-driven burr (Mitek, Norwood, MA), a mechanical shaver, and a bipolar radiofrequency (RF) wand on articular cartilage-covered condyles taken from sheep cadavers that were induced to have an osteoarthritic-like condition, and corresponding healthy control tissue. TYPE OF STUDY: Experimental designed animal cadaveric, biochemical, and histologic study. METHODS: Sheep condyles were used as a source of articular cartilage. Femurs were extracted approximately 1 hour postmortem and a transverse section of the condyles was made. Half of the samples were treated to induce an osteoarthritic-like condition. The condyles were then subjected to chondroplasty performed with the ExoJet high-pressure fluid-driven burr, a mechanical shaver, and a bipolar RF wand under sterile saline solution by an experienced orthopaedic surgeon. Twenty cross-sections from each condyle were examined by confocal microscopy to measure smoothness and depth of tissue damage to the articular cartilage caused by each of the 3 instruments. RESULTS: The ExoJet high-pressure fluid-driven burr and the bipolar RF wand left a smoother surface on the articular cartilage compared with the mechanical shaver. Additionally, the ExoJet fluid-burr caused slightly less tissue damage to the cartilage than the bipolar RF wand, both of which were less damaging than the shaver. CONCLUSIONS: Orthopaedists have multiple choices for surgical instruments used on cartilage. However, the effect on the integrity of the cartilage left remaining at the knee was previously unknown. Based on this study, a fluid-burr appears to leave the cartilage with a smaller zone of injury than does the RF wand or shaver. It also leaves the cartilage surface smoother than the shaver. During surgical procedures, minimizing cartilage breakdown and smooth remaining surfaces are desired because they minimize the vulnerable tissue to further destruction. A fluid burr leaves cartilage with less injury and with a smoother surface than do more traditional surgical instruments. CLINICAL RELEVANCE: This information should help surgeons in their selection of currently available surgical instruments and should aid engineers in the design of future instruments that function to modify articular cartilage.

Shaver, bipolar radiofrequency, and saline jet instruments for cutting meniscal tissue: a comparative experimental study on sheep menisci.

PURPOSE: The purpose of this study was to compare the quality of meniscal tissue cut with 3 different surgical instruments (traditional shavers, bipolar radiofrequency (RF) wands, and a high-pressure saline jet) and that of control menisci. TYPE OF STUDY: Experimental design, biochemical and histologic study. METHODS: Sixty samples of sheep menisci were separated into 4 groups. Three groups were shaved on the apical surface with the different instruments. The smoothness of the cut surfaces was evaluated visually by an orthopaedic surgeon and then scored by laser scanning cytometry and by line measurement analysis. The depth of tissue damage was measured by fluorescent cytochemistry. Means and standard deviations were calculated and comparative statistics used (P < .05). RESULTS: The edges cut by the saline jet and bipolar RF were significantly smoother when judged by the surgeon than those cut by traditional shaver. There was no significant difference between the saline jet and bipolar RF. There were no significant differences in smoothness when measured by laser scanning cytometry or by line measurement techniques. The control menisci had less depth of damage along the edge as measured by fluorescent cytochemistry than did any of the menisci cut with the instrument. The saline jet had significantly less depth of damage than did the shaver. No other significant differences existed between the instruments for depth of damage. CONCLUSIONS: The results of our investigation conclude that high-pressure saline instruments may cause less damage to residual meniscal tissue when compared with bipolar RF and shavers. Saline jets and bipolar RF also produce a smoother cut than shavers. CLINICAL RELEVANCE: Surgeons may want to consider the degree of residual damage to meniscal tissue from the application of various surgical instruments. Saline jets may be a superior cutting instrument than RF or shavers when considering depth of residual damage and smoothness of residual meniscal edges.

An anatomic evaluation of the active compression test.

The goal of this study was to describe the anatomic relationships present during the active compression test. Four pairs of cadaveric shoulders were positioned to simulate the active compression test. The shoulders were embedded in polyurethane and evaluated in the axial and coronal planes with a planer. In the axial plane, all internally rotated shoulders demonstrated contact between the lesser tuberosity and subscapularis tendon and the superior aspect of the glenoid and labrum. In the externally rotated position, there was no contact between the superior structures of the shoulder. In the coronal plane, the internally rotated specimens revealed contact between the supraspinatus tendon and the lateral aspect of the acromion. There was no contact between the supraspinatus tendon and the acromion when the shoulders were externally rotated in the coronal plane. The results demonstrate that the active compression test can be used to assist in the diagnosis of superior labrum anterior-posterior lesions as well as other shoulder pathology.

Electromyography of the quadriceps in patellofemoral pain with patellar subluxation.

This study compared muscle activity and timing of gait phases during functional activities in 13 subjects with patellofemoral pain associated with lateral subluxation and in 11 subjects with healthy knees. Fine wire electromyography recorded activity in the vastus lateralis and vastus medialis oblique during walking and ascending and descending stairs. Subjects were filmed to divide the activities into phases and determine timing. The vastus medialis oblique and vastus lateralis had similar patterns during all activities. Subjects with patellofemoral pain had significantly increased activity in the vastus medialis oblique and vastus lateralis compared with the healthy subjects during the most demanding phases of the gait cycle, suggesting a generalized quadriceps weakness in the patients with patellofemoral pain. Timing differences were seen in walking and stair ascending with the subjects with patellofemoral pain spending significantly more time in stance compared with the healthy subjects. This may be an attempt to reduce the load on weak quadriceps. These data reflect a generalized quadriceps muscle weakness, rather than the prevailing theory of quadriceps muscle imbalance as an etiology of patellofemoral pain. Therefore, we support the practice of strengthening the entire quadriceps muscle group, rather than attempting to specifically target the vastus medialis oblique.