Polymethyl Methacrylate for Elbow Arthroplasty: Is There Another Way?

Polymethyl methacrylate remains the only US Food and Drug Administration-approved method of total elbow arthroplasty fixation and exhibits high aseptic loosening rates that result in challenging revision surgeries and potential morbidity secondary to bone-cement implantation syndrome. In this policy paper, the authors aim to explore the historical background of polymethyl methacrylate and the complications that arise in association with its use. We will review arthroplasty trends in the elbow and lower extremities and the challenges with the US Food and Drug Administration-approval process.

Metacarpal Arc Motion: Comparison of Different Measurement Methods.

Introduction The range of motion of the carpometacarpal (CMC) joints is difficult to assess in clinical practice. Materials and Methods The purpose of this study was to measure a precise range of motion measurement of the metacarpal arc during maximum palmar flexion of the fifth CMC joint in healthy persons with three different methods: optical, electrogoniometrical, and sonographical. Results The metacarpal arc motion measured with the optical technique was 24.9 degrees (standard deviation [SD]: 6.2 degrees), with the electrogoniometric technique was 24.3 degrees (SD: 3.6 degrees) and with sonography was 25.1 degrees (SD: 3.5 degrees), with no differences between left and right hand for all methods. Conclusion This study shows that different techniques can be used for the measurement of the metacarpal arc motion. With these techniques, it is possible to assess the metacarpal arc in patients with fractures to the CMC joints to evaluate posttraumatic function und rehabilitation progress. This study shows level of evidence as III.

Quantifying the Center of Elbow Rotation: Implications for Medial Collateral Ligament Reconstruction.

BACKGROUND: Medial collateral ligament (MCL) reconstruction of the elbow mandates precise characterization of where the centerline of elbow rotation projects onto the medial epicondyle (ME). A muscle-splitting approach allows the flexor-pronator muscles to remain attached to the ME and facilitates visualization of the MCL remnant, the sublime tubercle, and the ulnohumeral joint line. Knowledge of where the centerline of rotation intersects the ME relative to the ulnohumeral joint line may assist the surgeon during placement of the proximal drill hole. METHODS: Models were created from the computed tomography scans of 29 normal elbows. The centerline of rotation, center of the trochlea, sublime tubercle, and ulnohumeral joint line were identified. Measurements were taken from the ulnohumeral joint line to the center of the trochlea and to the centerline of rotation in the sagittal view and along the course of the MCL. RESULTS: The centerline of rotation intersected the ME in a consistent location. With the elbow flexed 90°, the trochlea center and the centerline of rotation are essentially in line with each other. There are significant differences between the distances from the ulnohumeral joint line to the center of the trochlea and to the centerline of rotation in both the sagittal view and along the course of the MCL. CONCLUSIONS: The centerline of rotation is located 14.31 mm (1.70) from the ulnohumeral joint line in the sagittal view and 16.54 mm (2.09) from the ulnohumeral joint line along the course of the MCL.

Treatment of scaphoid waist fractures with the HCS screw.

The aim of the study was to evaluate the clinical results of the Headless Compression Screw (HCS, Synthes) when used for treatment of acute scaphoid waist fractures. The new screw design generates interfragmentary compression with use of a compression sleeve. Twenty-one patients were treated for acute scaphoid waist fractures type B2 with HCS screws. The average time to the final follow-up examination was 12.8 months. All 21 fractures united after a mean time of 7.2 weeks. The mean DASH score was 7.1. The average motion of the wrist in extension was 61°, flexion was 46°, radial abduction reached 25° and the ulnar abduction was 31°. The maximally achieved grip strength was 86% compared to the uninjured side. Treatment of type B2 scaphoid fractures with the Headless Compression Screw showed good functional and radiographic results. The results are similar to those identified using other screw fixation systems.

Motion deficit of the thumb in CMC joint arthritis.

PURPOSE: Idiopathic osteoarthritis (OA) of the thumb carpometacarpal (CMC) joint is a common disabling disease that often causes pain and motion loss. The aims of this study were to characterize the multidimensional motion capability of the thumb CMC joint in a group with severe CMC OA and to compare it with a control group. METHODS: We included 15 subjects with stage III/IV CMC OA according to the Eaton/Littler classification, and 15 control subjects. A motion analysis system using surface markers was employed to quantify the maximum boundary of the thumb circumduction envelope during repetitive thumb movements. We measured the area enclosed by the angular circumduction envelope and the ranges of motion (ROM) in multiple directions for the thumb CMC joint. RESULTS: Thumb osteoarthritis of the CMC joint stage III/IV resulted in a significantly smaller ROM in flexion/extension (45 degrees +/- 11 degrees for the CMC OA group, 59 degrees +/- 10 degrees for the controls), abduction-adduction (37 degrees +/- 6 degrees for the CMC OA group, 63 degrees +/- 13 degrees for the controls), and pronation-supination (49 degrees +/- 10 degrees for the CMC OA group, 62 degrees +/- 11 degrees for the controls) (p < .01). When analyzing the motion directions in flexion-extension and abduction-adduction separately, there was only a loss of extension and adduction (p < .01). CONCLUSIONS: Severe stages of thumb CMC OA cause an asymmetrical motion deficit with decreased ROM in extension and adduction, leading to decreased capability of counteropposition.

Wrist circumduction reduced by finger constraints.

PURPOSE: Assessment of wrist motion is important in diagnosing and treating motion impairment after injuries to the wrist. Little is known of how finger posture influences the movement of the wrist. The aim of this study was to investigate the effect of finger constraints on the maximum circumduction movement of the wrist. METHODS: Fifteen male right-handed subjects performed maximal circumferential wrist movements under 4 finger conditions: unconstrained fingers, holding a large cylinder (50 mm diameter), holding a small cylinder (25 mm diameter), and closed fist position. The wrist motion was captured by a surface marker-based motion analysis system. To quantify wrist motion capability, we constructed the maximal boundaries of wrist motion (circumduction envelope) from angular plots in flexion-extension (FE) and radial-ulnar deviation (RUD). The ranges of motion in FE and RUD and the envelope area were calculated. RESULTS: Finger constraints significantly reduced motion ranges in flexion and ulnar deviation, but not in extension and radial deviation. In comparison to the unconstrained finger condition, the motion ranges in flexion decreased by 13%, 16%, and 27% for the large cylinder, small cylinder, and fist conditions, respectively. The range of ulnar deviation was reduced by 10% for the large and small cylinder conditions and by 11% for the fist condition. The overall mobility in FE and RUD, as quantified by the area of circumduction envelope, decreased by 15%, 15%, and 23% for the large cylinder, small cylinder, and fist conditions, respectively. CONCLUSIONS: Wrist mobility is facilitated by the synergistic motion of finger joints. Constraining fingers in static flexion posture reduces wrist flexion and ulnar deviation without decreasing extension and radial deviation. A clinical implication is that wrist motion should be assessed under standardized finger joint configuration.

Distal radius fracture management in elderly patients: a literature review.

Distal radius fracture management in elderly patients remains without consensus regarding the appropriate treatment or anticipated outcome. Forty-one studies that included at least 10 patients with a minimum mean age of 65 years and that were indexed in Medline or Embase were reviewed. Treatment methods included pins and plaster, external fixation, K-wires, bone cement, and open reduction and internal fixation with plates. The methodological quality of each study was evaluated through use of a grading scale. Despite study heterogeneity, higher rates of infection were noted with external fixation and K-wire stabilization. Stratifying patients into low-demand and high-demand groups may improve the management of distal radius fractures in elderly patients. In sedentary patients with low demands, functional outcomes are good despite the presence of deformity. Patients with higher demands may benefit from fracture stabilization with locking volar plates. Volar plating with fixed-angle screws may be particularly suitable for elderly patients who may take longer to heal a fracture, be more susceptible to pin-track infection, and demonstrate earlier tendon irritation leading to rupture.