Kenneth J. Faber

Serratus anterior muscle activity during selected rehabilitation exercises

The purpose of this study was to document the electromyographic activity and applied resistance associated with eight scapulohumeral exercises performed below shoulder height. We used this information to design a continuum of serratus anterior muscle exercises for progressive rehabilitation or training. Five muscles in 20 healthy subjects were studied with surface electrodes for the following exercises: shoulder extension, forward punch, serratus anterior punch, dynamic hug, scaption (with external rotation), press-up, push-up plus, and knee push-up plus. Electromyographic data were collected from the middle serratus anterior, upper and middle trapezius, and anterior and posterior deltoid muscles. Each exercise was partitioned into phases of increasing and decreasing force and analyzed for average and peak electromyographic amplitude. Resistance was provided by body weight, an elastic cord, or dumbbells. The serratus anterior punch, scaption, dynamic hug, knee push-up plus, and push-up plus exercises consistently elicited serratus anterior muscle activity greater than 20% maximal voluntary contraction. The exercises that maintained an upwardly rotated scapula while accentuating scapular protraction, such as the push-up plus and the newly designed dynamic hug, elicited the greatest electromyographic activity from the serratus anterior muscle.

Proximal humeral fractures: A systematic review of treatment modalities

A systematic review was conducted of primary intervention of proximal humeral fracture, which is a common injury with significant morbidity. Keywords of proximal humeral fracture were entered into PubMed and Embase databases. Two evaluators reviewed abstracts from 1985 to 2004 for inclusion and exclusion criteria yielding 66 articles. These articles were evaluated independently for outcomes and quality of evidence using the Structured Effectiveness Quality Evaluation Scale and Sacketts Levels of Evidence. Patient characteristics and outcomes were recorded. The 66 studies included 2155 patients grouped by fracture types according to the Neer classification system. Studies differed by intervention, methods, outcome measures and results. Quality scores averaged 15/48; only 2 articles included randomized groups. Current studies typically lack randomization, comparators, and independent evaluation, with a resultant inability to produce clinical conclusions. Further research comparing primary treatment methods in a properly designed and controlled fashion is required, ideally using randomized controlled trials.

Comminuted radial head fractures treated with a modular metallic radial head arthroplasty : Study of outcomes

BACKGROUND Comminuted fractures of the radial head are challenging to treat with open reduction and internal fixation. Radial head arthroplasty is an alternative treatment with results that compare favorably with those reported after open reduction and internal fixation of similar fractures. The purpose of this study was to evaluate the two-year outcomes and the rate of recovery of a closely followed cohort of patients in whom an unreconstructible radial head fracture had been treated with a modular metallic prosthesis. METHODS Twenty-six patients (seventeen female and nine male; mean age, fifty-four years) with an unreconstructible comminuted radial head fracture and associated elbow injuries were treated with a modular metallic radial head arthroplasty. Patients who had presented more than four weeks following the injury or had had the radial head arthroplasty as a second-stage or salvage procedure were excluded. Of the twenty-six patients, twenty-two had an associated elbow dislocation, and thirteen of them also had an associated fracture of the coronoid process. Patients were prospectively followed at three, six, twelve, and twenty-four months. Self-reported limb function, general health, range of motion, and isometric strength were assessed by an independent observer. RESULTS Following treatment of the injury, significant decreases in self-reported and measured impairments were noted over time, with the majority of the recovery occurring by six months and little further recovery noted between six and twenty-four months. There were slight-to-moderate deficits in the range of motion and strength compared with the values on the contralateral, unaffected side. Patient satisfaction was high at three months and remained high at two years. All elbow joints remained stable, no implant required revision, and there was no evidence of overstuffing of the joint. Mild osteoarthritis was seen in five (19%) of the twenty-six patients. CONCLUSIONS An arthroplasty with a modular metallic radial head is a safe and effective option for the treatment of unreconstructible radial head fractures associated with other elbow injuries. Recovery primarily occurs by six months, with minimal additional improvements over the next eighteen months.

Pull-Out Strength and Stiffness of Meniscal Repair Using Absorbable Arrows or Ti-Cron Vertical and Horizontal Loop Sutures

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.

Outcome after open reduction and internal fixation of capitellar and trochlear fractures

BACKGROUND Capitellar and trochlear fractures are uncommon fractures of the distal aspect of the humerus. There is limited information about the functional outcome of patients managed with open reduction and internal fixation. METHODS The functional outcome of twenty-eight patients, with a mean age (and standard deviation) of 43 +/- 13 years, who were treated with open reduction and internal fixation for capitellar and trochlear fractures was evaluated at a mean duration of follow-up of 56 +/- 33 months. Patient outcomes were assessed with physical and radiographic examination, range-of-motion measurements, strength testing, and self-reported questionnaires (Short Form-36, Mayo Elbow Performance Index, American Shoulder and Elbow Surgeons Elbow Assessment Form, and Patient-Rated Elbow Evaluation scales). RESULTS Eleven fractures involved the capitellum with or without fracture of the lateral ridge of the trochlea, four involved the capitellum and trochlea as one piece, and thirteen involved the capitellum and trochlea as separate fragments. These fractures were further characterized by the presence or absence of posterior comminution. Fourteen patients had isolated fractures, and fourteen had other elbow, forearm, or wrist injuries. Patients with more complex fractures required more extensive surgery, had more complications resulting in secondary procedures, and had poorer outcomes compared with those with simple fractures. The average score on the Mayo Elbow Performance Index (91 +/- 11), the average quality-of-life scores (46 on the physical component and 50 on the mental component of the Short Form-36), and the average range of motion (19 degrees to 138 degrees ) suggest favorable patient outcomes overall. Two comminuted fractures did not unite and required conversion to a total elbow arthroplasty. CONCLUSIONS Patients with isolated noncomminuted capitellar and/or trochlear fractures have better results than those with more complex fractures. A classification system based on the radiographic patterns of these fractures is recommended.

Occult Osteochondral Lesions After Anterior Cruciate Ligament Rupture Six-Year Magnetic Resonance Imaging Follow-up Study

Twenty-three patients with acute anterior cruciate ligament injuries, normal radiographs, and occult osteochondral lesions revealed by magnetic resonance imaging were reviewed 6 years after initial injury and anterior cruciate ligament hamstring autograft reconstruction. Each patient completed the Mohtadi Quality of Life outcome measure for anterior cruciate ligament deficiency, underwent clinical examination, and had a repeat magnetic resonance imaging scan. The index and follow-up magnetic resonance imaging scans were compared with respect to cartilage thinning and marrow signal. A significant number of patients had evidence of cartilage thinning adjacent to the site of the initial osteochondral lesion. Marrow signal changes persisted in 15 (65%) of the patients. Clinical comparison of patients with normal cartilage with those who had cartilage thinning revealed similar results on both KT-1000 arthrometry and on the Mohtadi outcome measure. This suggests that the initial injury resulted in irreversible changes in the knee. Injuries causing marrow signal changes may result in an alteration in the load-bearing properties of subchondral bone, which in turn allow for changes in the overlying cartilage. Further follow-up will determine the clinical significance of changes detected by magnetic resonance imaging.

Chronic Posttraumatic Elbow Disorders Treated with Metallic Radial Head Arthroplasty

BACKGROUND Metallic radial head arthroplasty is a proven technique for the treatment of complex radial head fractures. The purpose of this study was to evaluate the functional outcomes of a metallic radial head arthroplasty in patients with chronic posttraumatic elbow disorders. METHODS The results of thirty-two metallic radial head arthroplasties in thirty-two consecutive patients were retrospectively reviewed. The indications for the radial head arthroplasty included posttraumatic nonunion and malunion of the radial head, elbow instability following previous excision of the radial head, and failure of a silicone radial head implant used to treat an acute radial head fracture. The study included thirteen male and nineteen female patients followed for a minimum of two years. The radial head arthroplasties were performed at an average of 2.4 years after the injury. Analysis included chart review, personal interview, physical examination, radiographic examination, and strength testing as well as the administration of general and region-specific questionnaires. RESULTS The mean duration of follow-up was eight years. The average Mayo Elbow Performance Score was 83 of 100 points, with seventeen (53%) of the thirty-two results rated as excellent; four (13%), as good; seven (22%), as fair; and four (13%), as poor. The average score for subjective patient satisfaction was 8.5 points on a 10-point scale. Patients had significantly less motion and strength in the affected elbow than in the unaffected elbow. Seventy-four percent of the patients demonstrated some degree of posttraumatic arthritis. There were no significant differences in ulnar variance and the ulnohumeral joint space between the affected and unaffected arms. Over the course of the study, no metallic radial head arthroplasties required revision. CONCLUSIONS Metallic radial head arthroplasty for the treatment of posttraumatic elbow disorders appears to be a safe and durable procedure that can provide a functional range of motion and pain relief for at least five to ten years. However, longer follow-up is needed to evaluate progression of lucencies adjacent to stems and osteoarthritis.

Radial Head Fractures—An Update

Radial head fractures are the most common fractures occurring around the elbow. Although radial head fractures can occur in isolation, associated fractures and ligament injuries are common. Assembling the clinical presentation, physical examination, and imaging into an effective treatment plan can be challenging. The characteristics of the radial head fracture influence the technique used to optimize the outcome. Fragment number, displacement, impaction, and bone quality are considered when deciding between early motion, fragment excision, and radial head excision, repair, or replacement. Isolated, minimally displaced fractures without evidence of mechanical block can be treated nonsurgically with early active range of motion (ROM). Partial, displaced radial head fractures without evidence of mechanical block can be treated either nonsurgically or with open reduction internal fixation (ORIF), as current evidence does not prove superiority of either strategy. For displaced fractures with greater than 3 fragments, radial head replacement is recommended. Radial head arthroplasty may be preferred over tenuous fracture fixation in the setting of associated ligament injuries when maintenance of joint stability could be compromised by ineffective fracture fixation.

Determination of Correct Implant Size in Radial Head Arthroplasty to Avoid Overlengthening

BACKGROUND Insertion of a radial head implant that results in radial overlengthening has been associated with altered elbow kinematics, increased radiocapitellar joint forces, capitellar erosions, early-onset arthritis, and loss of elbow flexion. The purpose of this study was to identify clinical and radiographic features that may be used to diagnose overlengthening of the radius intraoperatively and on postoperative radiographs. METHODS Radial head implants of varying thicknesses were inserted into seven cadaver specimens, which were then assessed clinically and radiographically. Eight stages were examined: the intact specimen (stage 1); repair of the lateral collateral ligament (stage 2); radial head resection with repair of the lateral collateral ligament (stage 3); insertion of an implant of the correct thickness (stage 4); and insertion of an implant that resulted in radial overlengthening of 2 mm (stage 5), 4 mm (stage 6), 6 mm (stage 7), or 8 mm (stage 8). The specimens were tested with and without muscle loading to simulate resting muscle tone and surgical paralysis, respectively. At each stage, radiographs were made to measure the ulnohumeral joint space and the lateral ulnohumeral joint was visually assessed. RESULTS We identified no difference, with regard to medial ulnohumeral joint incongruity as seen radiographically, among stages 1 through 6 during the tests with muscle loading. A significant difference in medial ulnohumeral joint incongruity was found in stages 7 (p = 0.003) and 8 (p < 0.001). The clinical (visually assessed) lateral ulnohumeral joint space gap was negligible in stages 1 through 4 but increased significantly at all stages involving overlengthening (gross gap, 0.9 mm with 2 mm of overlengthening [p = 0.005], 2.3 mm with 4 mm of overlengthening [p < 0.001], 3.4 mm with 6 mm [p < 0.001], and 4.7 mm with 8 mm [p < 0.001]). CONCLUSIONS Incongruity of the medial ulnohumeral joint becomes apparent radiographically only after overlengthening of the radius by >or=6 mm. Intraoperative visualization of a gap in the lateral ulnohumeral joint is a reliable indicator of overlengthening following the insertion of a radial head prosthesis.

Open Reduction Internal Fixation Versus Percutaneous Pinning With External Fixation of Distal Radius Fractures: A Prospective, Randomized Clinical Trial

PURPOSE The purpose of this randomized clinical trial was to investigate the functional outcomes of the surgical treatment of distal radius fractures, comparing treatment by external fixation and percutaneous pinning to open reduction and internal fixation (ORIF) using a plate. METHODS We randomized 53 patients with distal radius fractures that failed closed reduction and casting to ORIF (n = 27) or external fixation (n = 26). For pragmatic reasons, the choice of ORIF was left to the surgeons discretion (early recruitment, dorsal plates [n = 9]; later recruitment, volar locked plates [n = 18]). Outcomes were measured before surgery, at 6 weeks, and at 3, 6, and 12 months and included the Patient-Rated Wrist Evaluation (PRWE); Disabilities of the Arm, Shoulder, and Hand; range of motion; grip strength; and serial radiographic analysis. Generalized linear modeling using repeated measures was used to identify differences in outcome scores between fixation types over time. Other continuous variables were analyzed using the Student t-test or one-way analysis of variance for multiple groups. RESULTS There were no differences in the demographic characteristics or fracture severity between groups. Based on generalized linear modeling, on average, the ORIF group scored 11 points lower on the PRWE across all time points compared to the external fixation group. The PRWE detected higher pain and disability with external fixation before surgery, at 6 weeks, and at 3 months. Using generalized linear modeling, a post hoc subgroup analysis identified significantly better (15-point advantage) PRWE scores averaged across all time points with volar locking plates compared to both external fixation and dorsal plating. CONCLUSIONS The PRWE scores were significantly lower for patients treated with ORIF compared to those with external fixation, with the best outcomes observed with volar locking plates. These advantages were observed in the early postoperative period, and overall scores equalized at 1 year. A higher mean initial preoperative PRWE score was seen with external fixation, perhaps indicating a more severe initial injury. Given this difference, the interpretation of these results is not clear.