Peter B. MacDonald

Knee strength deficits after hamstring tendon and patellar tendon anterior cruciate ligament reconstruction.

PURPOSE The purpose of this study was to examine the strength of the knee flexors and knee extensors after two surgical techniques of ACL reconstruction and compare them to an age and activity level matched control group. METHODS Twenty-four subjects who had undergone ACL reconstruction greater than 1 yr previously were placed into one of two groups according to autograft donor site: patellar tendon (BPB; N = 8) and hamstring (H; N = 16), and compared with an active, control group (N = 30). Knee flexor and extensor strength was evaluated using isovelocity dynamometry (5 speeds, eccentric and concentric, 5-95 degrees ROM). Strength maps were used to graphically analyze strength over a broad operational domain of the neuromuscular system. Average strength maps were determined for each autograft group and compared with controls. A difference map (control minus graft group) and confidence (t-test) maps were used to quantitatively identify strength deficits. RESULTS The combined ACL group (N = 24) revealed a global 25.5% extensor strength deficit, with eccentric regional (angle and velocity matched) deficits up to 50% of control. Strength deficits covered over 86% of the sampled strength map area (P < 0.01). These knee extensor strength deficits are greater than previously reported. In addition, the BPB group demonstrated a concentric, low velocity, knee extensor strength deficit at 60-95 degrees that was not observed in the H group. Significant graft site dependent, regional knee flexor deficits of up to 50% of control were observed for the H group. CONCLUSIONS Strength deficits localized to specific contraction types and ranges of motion were demonstrated between the ACL and control groups that were dependent upon autograft donor site. Postoperative rehabilitation protocols specific to these deficits should be devised.

Arthroscopic Rotator Cuff Repair with and without Acromioplasty in the Treatment of Full-thickness Rotator Cuff Tears: A Multicenter, Randomized Controlled Trial

BACKGROUND The primary objective of this prospective randomized controlled trial was to compare functional and quality-of-life indices and rates of revision surgery in arthroscopic rotator cuff repair with and without acromioplasty. METHODS Eighty-six patients consented and were randomly assigned intraoperatively to one of two study groups, and sixty-eight of them completed the study. The primary outcome was the Western Ontario Rotator Cuff (WORC) index. Secondary outcome measures included the American Shoulder and Elbow Surgeons (ASES) shoulder assessment form and a count of revisions required in each group. Outcome measures were completed preoperatively and at three, six, twelve, eighteen, and twenty-four months after surgery. RESULTS WORC and ASES scores improved significantly in each group over time (p < 0.001). There were no differences in WORC or ASES scores between the groups that had arthroscopic cuff repair with or without acromioplasty at any time point. There were no differences in scores on the basis of acromion type, nor were any interaction effects identified between group and acromion type. Four participants (9%) in the group that had arthroscopic cuff repair alone, one with a Type-2 and three with a Type-3 acromion, required additional surgery by the twenty-four-month time point. The number of patients who required additional surgery was greater (p = 0.05) in the group that had arthroscopic cuff repair alone than in the group that had arthroscopic cuff repair and acromioplasty. CONCLUSIONS Our findings are consistent with previous research reports in which there was no difference in functional and quality-of-life indices for patients who had rotator cuff repair with or without acromioplasty. The higher reoperation rate was found in the group without acromioplasty. Further study that includes follow-up imaging and patient-reported outcomes over a greater follow-up period is needed.

The efficacy of magnetic resonance imaging in acute knee injuries.

ObjectiveTo evaluate the clinical efficacy of magnetic resonance imaging (MRI) of the knee in acute injuries with indeterminate clinical findings, using arthroscopy as a gold standard. DesignA prospective double-blind study was performed. All patients underwent MRI on a 1.5 T magnet using dual spin echo pulse sequences. This was followed by arthroscopy. SettingTertiary care referral center. PatientsTwenty-three patients with an average age of 26 years satisfied the study criteria. Patients had to have been seen by one of two orthopaedic surgeons within 6 weeks of sudden trauma to the knee complicated by a hemarthrosis, clinical assessment of which was equivocal. ResultsThe respective sensitivity and specificity for MRI of the knee were 90% (18/20) and 67% (2/3) for detecting any anterior cruciate ligament injury, 50% (1/2) and 86% (18/21) for detecting medial meniscal tears, and 88% (7/8) and 73% (11/15) for detecting lateral meniscal tears. MRI also identified injuries that could not be assessed on arthroscopy, including 14 bone bruises, five posterior cruciate ligament tears, nine medial collateral ligament tears, and one lateral collateral ligament tear. The detection of composite injury requiring surgical intervention yielded a sensitivity of 100% (16/16) and a specificity of 71% (5/7). Prospective use of MRI evaluation of the knee could have prevented 22% (5/23) of diagnostic arthroscopic procedures. ConclusionEquivocal clinical findings in patients with acute knee injury should lead to use of MRI in an appropriate clinical setting. To our knowledge a prospective study of the efficacy of MRI of the knee in this patient population has not been reported. In the presence of such inclusion criteria, the results of our study support the use of early MRI to guide further surgical management.

A Multicenter Randomized Controlled Trial Comparing Single-Row with Double-Row Fixation in Arthroscopic Rotator Cuff Repair

BACKGROUND Controversy exists regarding the optimal technique for arthroscopic rotator cuff repair. The purpose of this multicenter, randomized, double-blind controlled study was to compare the functional outcomes and healing rates after use of single-row and double-row suture techniques for repair of the rotator cuff. METHODS Ninety patients undergoing arthroscopic rotator cuff repair were randomized to receive either a single-row or a double-row repair. The primary objective was to compare the Western Ontario rotator cuff index (WORC) score at twenty-four months. Secondary objectives included comparison of the constant and american shoulder and elbow surgeons (ASES) scores and strength between groups. Anatomical outcomes were assessed with magnetic resonance imaging (MRI) or ultrasonography to determine the postoperative healing rates. RESULTS Baseline demographic data including age (p = 0.29), sex (p = 0.68), affected side (p = 0.39), and rotator cuff tear size (p = 0.28) did not differ between groups. The WORC score did not differ significantly between groups at any time point (p = 0.48 at baseline, p = 0.089 at three months, p = 0.52 at six months, p = 0.83 at twelve months, and p = 0.60 at twenty-four months). The WORC score at each postoperative time point was significantly better than the baseline value. The Constant score, ASES score, and strength did not differ significantly between groups at any time point. Logistic regression analysis demonstrated that a smaller initial tear size and double-row fixation were associated with higher healing rates. CONCLUSIONS No significant differences in functional or quality-of-life outcomes were identified between single-row and double-row fixation techniques. A smaller initial tear size and a double-row fixation technique were associated with higher healing rates as assessed with ultrasonography or MRI. LEVEL OF EVIDENCE Therapeutic level I. See Instructions for Authors for a complete description of levels of evidence.

Hamstring and quadriceps strength balance in normal and hamstring anterior cruciate ligament-reconstructed subjects.

Objective:The purpose of this study was to evaluate and characterize the agonist-antagonist strength balance (hamstring/quadriceps [H/Q] ratio and dynamic control ratio [DCR]) about the knee specific to velocity, range of motion, and contraction type. We hypothesized that there would be systematic variation in the H/Q ratio and DCR based on knee joint angle, angular velocity, and contraction type. We also hypothesized that these ratios would be altered in the anterior cruciate ligament (ACL)-reconstructed group in favor of protecting the ACL graft (relative knee flexor strength when strain on the ACL is the greatest). Design:Cross-sectional design. Setting:A tertiary care sport medicine clinic. Patients or Participants:Sixteen subjects more than 1 year after hamstring tendon ACL reconstruction were compared with 30 active uninjured control subjects. Interventions:Isokinetic strength testing was performed over 5° to 95° knee joint range of motion, 5 angular velocities (50, 100, 150, 200, 250°/s), for concentric and eccentric contractions. Main Outcome Measurements:Angle and velocity-matched H/Q ratio maps and DCR maps were produced for each group. Difference maps allowed quantification of the differences between the groups. Results:Angle and velocity-matched H/Q ratio maps demonstrated systematic variation based on joint angle, velocity, and contraction type for both the control (H/Q, ~0–1.42; DCR, ~0–1.57) and the ACL-reconstructed group (H/Q, ~0–1.33; DCR, ~0–1.35). Difference maps demonstrate regional (angle and velocity-specific) alteration in the ratio between the ACL-reconstructed and control groups. Conclusions:Specific imbalances were demonstrated in the ACL-reconstructed group compared with control. In high knee flexion angles, the low H/Q ratio may represent a compromised ability of the hamstrings to stabilize the knee joint throughout the full range of motion. Near full knee extension shifts in favor of the knee flexors may represent an attempt to stabilize the knee at the angle of greatest ACL strain. These finding have implications for graft donor site selection and postoperative rehabilitation as well as provide insight into the neuromuscular control of the knee.

Comprehensive functional analysis of shoulders following complete acromioclavicular separation.

The purpose of this study was to examine the results of the two major methods of treatment of complete acromioclavicular separation: surgery and nonsurgical techniques. Twenty male patients with complete acro mioclavicular separation within the preceding 13 months were retrospectively examined and tested for recovery of shoulder strength and function. Compari sons were conducted between 10 of the patients who had been treated nonsurgically (Group 1), and 10 who had been treated surgically (Group 2). An additional group of 10 uninjured male subjects as controls was also tested for comparison of strength between domi nant and nondominant limbs (Group 3). All of the pa tients were tested for strength of both shoulders using the Kin-Com isokinetic dynamometer, for shoulder flex ibility using the Leighton flexometer, and for grip strength using a standard grip dynamometer. A ques tionnaire concerning patient evaluation of the injury was also administered to all of the subjects. The majority of strength and flexibility tests showed no significant dif ferences between the nonsurgical and surgical groups. The nonsurgical group was statistically superior to the surgical group in the following test scores: eccentric abduction (fast speeds), concentric external rotation (slow speeds), eccentric external rotation (fast), eccen tric abduction (slow), and flexibility in external rotation. These findings generally indicated that the nonsurgical treatment of a third-degree acromioclavicular separa tion is superior in restoring normal shoulder function in the 1 st year following injury.

Reliability of radiographic assessment of acromial morphology

The most widely used radiographic classification system for acromial morphology identifies three distinct acromial shapes: type I (flat), type II (curved), and type III (hooked). The purpose of this study was to measure the interobserver and intraobserver reliability of determinations of acromial morphology as defined by this system. Between 1990 and 1992, one hundred twenty-six supraspinatus outlet radiographs were obtained from 126 patients by technicians from Triangle Orthopaedic Associates in Durham, N.C. Six fellowship-trained shoulder surgeons independently reviewed each radiograph and classified it as type I, II, or III on the basis of established guidelines. Two surgeons classified each film a second time in random order. Analysis of variance was performed to obtain coefficients for interobserver and intraobserver reliability. Consensus ratings were then used to classify the 126 radiographs into consensus type I, consensus type II, or consensus type III groups. Percentages of type I, II, and III individual ratings within each consensus group were determined. The intraobserver reliability coefficient was 0.888, interpreted as good to excellent reliability. The interobserver reliability coefficient was 0.516, interpreted as poor to fair reliability. Of the 126 radiographs, 26 (20.6%) were rated as consensus type I, 76 (60.3%) were rated as consensus type II, and 24 (19.1%) were rated as consensus type III. The reliability of observer ratings was lowest when delineation between acromial types II and III was required. The low interobserver reliability makes comparisons of studies by different authors difficult to interpret and obscures the true incidence of acromial morphologic types. It also questions reported correlations between acromial type and shoulder pathologic conditions. It is concluded that a system that incorporates more objective classification criteria and acknowledges the continuous nature of acromial morphologic types may improve interobserver reliability and validate the systems use in making clinical and surgical judgments.

The role of subacromial decompression in patients undergoing arthroscopic repair of full-thickness tears of the rotator cuff: a systematic review and meta-analysis.

PURPOSE The purpose of this study was to determine the efficacy of arthroscopic repair of full-thickness rotator cuff tears with and without subacromial decompression. METHODS We searched the Cochrane Central Register of Controlled Trials (third quarter of 2011), Medline (1948 to week 1 of September 2011), and Embase (1980 to week 37 of 2011) for eligible randomized controlled trials. Two reviewers selected studies for inclusion, assessed methodologic quality, and extracted data. Pooled analyses were performed by use of a random effects and relative risk model with computation of 95% confidence intervals. RESULTS We included 4 randomized trials and 373 patients. Methodologic quality was variable as assessed by the CLEAR NPT (Checklist to Evaluate a Report of a Non-pharmacological Trial) tool. One trial showed that there was no difference in disease-specific quality of life (Western Ontario Rotator Cuff questionnaire) between the 2 treatment groups. A meta-analysis of shoulder-specific outcome measures (American Shoulder and Elbow Surgeons or Constant scores) or the rate of reoperation between patients treated with subacromial decompression and those treated without it also showed no statistically significant differences. CONCLUSIONS On the basis of the currently available literature, there is no statistically significant difference in subjective outcome after arthroscopic rotator cuff repair with or without acromioplasty at intermediate follow-up. LEVEL OF EVIDENCE Level I, systematic review of Level I studies.

Diagnostic and treatment differences among experienced shoulder surgeons for instability conditions of the shoulder.

Objective:This study examines the effects of a low-intensity walking program on the quality of life in patients with Crohns disease. Design:Patients were randomized into exercise and nonexercise groups for a prospective study. Setting:Patients were recruited at the inflammatory bowel disease outpatient clinic at the London Health Science Center, London, Ontario. Patients:Thirty-two adult patients met the inclusion criteria of (1) mildly active disease or disease in remission, (2) habitual physical activity of less than 2 times per week of vigorous activity, (3) not anticipating change of dose or type of medication for Crohns disease, and (4) no history of cardiovascular disease. All 32 patients who entered the study completed the 3-month study. Intervention:Patients performed low-intensity walking at an interval of 3 times per week for a duration of 3 months. Each walking session lasted for 30 minutes. Main Outcome Measurements:The Inflammatory Bowel Disease Questionnaire, the Inflammatory Bowel Disease Stress Index, and the Harvey-Bradshaw Simple Index were used as outcome. Survey measurements were recorded at 1-month intervals on commencement of the walking program. Results:Patients in the exercise group experienced a statistically significant (P < 0.05) improvement in quality of life in all 3 of the outcome measurement questionnaires with no detrimental effects in terms of disease activity. Conclusion:A low-intensity walking program may have a beneficial effect in patients with Crohns disease and improve their quality of life with no exacerbations in disease symptoms.

Acromioclavicular and sternoclavicular joint injuries.

Acromioclavicular (AC) joint injuries are a frequent diagnosis following an acute shoulder injury. The literature on AC joint dislocation is extensive, reflecting the intense debate surrounding the topic. The choice of treatment is influenced by factors including the type of injury, the patients occupation, the patients past medical history, the acuity of the injury, and patient expectations. Sternoclavicular (SC) joint dislocation is an uncommon injury. The treatment of acute anterior SC joint dislocations is controversial. It is difficult to study with a well-designed prospective study because of the low frequency of this injury. Posterior dislocations are much less common than anterior dislocations. Posterior dislocations, however, are more serious; they are associated with significant complications and require prompt attention.