Three-dimensional characterization of trabecular bone mineral density of the proximal ulna using quantitative computed tomography.

BACKGROUND: Although previous studies have measured general proximal forearm bone mineral density (BMD), no study has systematically mapped the 3-dimensional trabecular BMD of the proximal ulna. The aim of this study was to describe the 3-dimensional distribution of the trabecular bone density of the proximal ulna. We hypothesize a variable distribution of proximal ulna trabecular BMD depending on the region of interest (ROI). METHODS: Computed tomographic (CT) scans of 9 fresh-frozen cadaveric proximal ulna specimens with a mean age of 59.3 ± 8.1 years were studied. Each CT file was converted from DICOM to a QCT file that could be analyzed using QCT software (QCT Pro Version 6.1, Model 4 CT Calibration Phantom; MindWays Software Inc, Austin, TX, USA). The ROIs were defined as spheres of trabecular bone 3 mm in diameter located throughout the proximal ulna. RESULTS: ROIs proximal to the trochlear notch demonstrated higher BMD than ROIs distal to the trochlear notch. Furthermore, volar ROIs adjacent to the ulnohumeral joint tended to have higher BMD than dorsal ROIs. The highest BMD was found in the tip of the olecranon. CONCLUSION: Hardware in fixation constructs for proximal ulnar fractures should be directed toward ROIs with the highest BMD to maximize purchase. Hardware should approach the ulnohumeral joint without penetrating the joint to capture trabecular bone with the highest BMD. The most important fixation in such a construct will be that which captures trabecular bone with maximum BMD proximal to the trochlear notch (eg, the tip of the olecranon).

Three-Dimensional Characterization of Trabecular Bone Mineral Density of the Distal Radius Utilizing Quantitative Computed Tomography.

Background: Distal radius (DR) fractures demonstrate patterns of predictable fragments. Bone mineral density (BMD) measurements of these regions of interest (ROIs) may guide more precise treatment. Methods: Computed tomography (CT) scans of the DR of 42 healthy volunteers (23 female) were analyzed using quantitative CT software, measuring BMD within trabecular bone. Seven ROIs were described by alignment with the distal (volar ulnar distal [VUD], dorsal ulnar distal [DUD], volar radial distal [VRD], and dorsal radial distal [DRD]) or proximal (middle ulnar proximal [MUP], middle proximal [MP], and middle radial proximal [MRP]) sigmoid notch. Additional ROIs were the radial styloid (RS) and metadiaphysis (MD). A general estimation equation assessed subject's BMDs with predictive factors of gender, ROI, and age. The interaction between gender, ROI, and age was included in the model to allow for differences in ROI to vary with gender and/or age. Results: Comparing ROIs within the same gender and, separately, within the same age group revealed significantly higher BMD adjacent to the radioulnar and radiocarpal joints. Male and female individuals aged ≥50 years (mean: 172.7 mg/cm3 ± 6.1) had significantly lower BMD than those aged <50 years (mean: 202.7 mg/cm3 ± 5.8) when all ROIs were considered. Males had higher mean BMD at each ROI compared with females; these differences were significant in 5 of the 9 ROIs: VUD, DUD, DRD, RS, MUP. Conclusions: Trabecular BMD of the DR is highest adjacent to the radioulnar and radiocarpal joints. Female patients and those ≥50 years have lower trabecular BMD.

Utility of Prolotherapy for Upper Extremity Pathology.

Prolotherapy is a method of treatment of painful musculoskeletal conditions whereby a sclerosing agent is injected into an area of tendinosis or osteoarthritis to strengthen and repair painful connective tissue. It is a safe, effective, and relatively inexpensive nonsurgical treatment modality. This article provides a history of prolotherapy, discusses its proposed mechanisms of action, and provides a review of the existing literature on prolotherapy as a treatment for upper extremity pathologies, specifically, hand osteoarthritis, lateral epicondylitis, and rotator cuff disease.

Ulnar Styloid Base Fractures Cause Distal Radioulnar Joint Instability in a Cadaveric Model.

BACKGROUND: The deep portion of the distal radioulnar ligaments (DRUL) inserts on the ulnar fovea and is the most important stabilizer of the distal radioulnar joint (DRUJ). Ulnar styloid base fractures that include the ulnar fovea may cause DRUJ instability. METHODS: DRUJ stability in pronosupination was evaluated in 12 fresh-frozen upper extremities (4 female) aged 52 to 68 years (mean: 58.8 years) using a custom fixture, which allowed free rotation of the radius around the fixed ulna. Optical motion capture was used to record rotation of the radius with respect to the ulna. Each specimen was subjected to 3 N m of torque in both supination and pronation under 4 conditions: intact, ulnar styloid osteotomy with disruption of the foveal insertion of the DRUL, ulnar styloid fixation, and DRUL transection. Group differences were compared using a 1-way repeated-measures analysis of variance and Tukey multiple comparison post hoc tests. RESULTS: When compared with the intact condition, both ulnar styloid osteotomy and DRUL transection significantly increased mean pronation (by 9.40° and 15.21°, respectively) and supination (by 9.05° and 17.42°, respectively) of the forearm. Screw fixation only significantly reduced pronation compared with osteotomy (by 2.62°). Screw fixation did not significantly affect supination. CONCLUSIONS: Ulnar styloid fractures that disrupt the fovea cause instability of the DRUJ in pronation and supination under 3 N m of torque in a cadaveric model. Screw fixation of ulnar styloid base fractures achieves anatomic reduction; however, it only partially returns rotational stability acutely to the DRUJ and only during pronation.

Evaluation of Ulnar-sided Wrist Pain.

Determining the etiology of ulnar-sided wrist pain is often challenging. The condition may be acute or chronic, and differential diagnoses include injuries to the ulnar carpal bones, ligament tears, tendinitis, vascular conditions, osteoarthritis and systemic arthritis, and ulnar nerve compression. An anatomically based, methodical physical examination coupled with provocative maneuvers, including piano key, ulnar impaction, shuck, foveal stress, and extensor carpi ulnaris synergy tests, further defines the differential diagnosis. Diagnostic imaging used in the evaluation of ulnar-sided wrist pain includes plain radiographs and MRI with or without arthrography. Wrist arthroscopy is becoming increasingly important in the diagnosis and management of ulnar-sided intra-articular wrist pathology.

Patient Comprehension of Carpal Tunnel Surgery: An Investigation of Health Literacy.

Background: Health literacy is the ability of a patient to understand their medical condition. The purpose of this investigation is to determine whether patients are able to obtain an elementary understanding of the fundamental principles of carpal tunnel release and the postoperative instructions after going through the process of informed consent and being provided an additional standardized postoperative instruction document. Our hypothesis is that patients will lack an understanding of these principles and, therefore, will be at risk for being noncompliant in their postoperative care. Methods: Fifty patients with a diagnosis of carpal tunnel surgery who elected to undergo carpal tunnel release alone were enrolled. A standardized education process was performed. Patients completed the questionnaire at their postoperative visit. Results: The average percentage of correct answers was 75.8% (8.34 out of 11 correct). Fisher exact test analysis demonstrated that patients with a lower education level were less likely to know how long it takes for their preoperative symptoms to resolve (P = .0071), and they were less likely to correctly choose all of the important elements of postoperative care during the first week after surgery (P = .022). Conclusions: Although we made efforts to help patients achieve health literacy in carpal tunnel surgery, we found that patients continued to lack comprehension of pertinent components of carpal tunnel surgery, particularly understanding the involved anatomy.

Trends in Revision Elbow Ulnar Collateral Ligament Reconstruction in Professional Baseball Pitchers.

PURPOSE: To determine the frequency of revision elbow ulnar collateral ligament (UCL) reconstruction in professional baseball pitchers. METHODS: Data were collected on 271 professional baseball pitchers who underwent primary UCL reconstruction. Each player was evaluated retrospectively for occurrence of revision UCL reconstructive surgery to treat failed primary reconstruction. Data on players who underwent revision UCL reconstruction were compiled to determine total surgical revision incidence and revision rate by year. The incidence of early revision was analyzed for trends. Average career length after primary UCL reconstruction was calculated and compared with that of players who underwent revision surgery. Logistic regression analysis was performed to assess risk factors for revision including handedness, pitching role, and age at the time of primary reconstruction. RESULTS: Between 1974 and 2014, the annual incidence of primary UCL reconstructions among professional pitchers increased, while the proportion of cases being revised per year decreased. Of the 271 pitchers included in the study, 40 (15%) required at least 1 revision procedure during their playing career. Three cases required a second UCL revision reconstruction. The average time from primary surgery to revision was 5.2 ± 3.2 years (range, 1-13 years). The average length of career following primary reconstruction for all players was 4.9 ± 4.3 years (range, 0-22 years). The average length of career following revision UCL reconstruction was 2.5 ± 2.4 years (range, 0-8 years). No risk factors for needing revision UCL reconstruction were identified. CONCLUSIONS: The incidence of primary UCL reconstructions among professional pitchers is increasing; however, the rate of primary reconstructions requiring revision is decreasing. Explanations for the decreased revision rate may include improved surgical technique and improved rehabilitation protocols. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

Dual-camera technique for arthroscopic rotator cuff repair.

An all-arthroscopic rotator cuff repair demands a high level of technical skill and is associated with a steep learning curve. It is well accepted that small rotator cuff tears or partial tears can be more difficult than large or even massive tears to repair. Part of the reason is the difficulty in visualizing the tear, as well as important surrounding structures, during repair. To improve visibility during the repair process, we have introduced a second arthroscopic camera. Two cameras allow the surgeon to observe the rotator cuff from both the articular and bursal sides. We find this technique has merit in small or partial-thickness rotator cuff tears; however, there may be other applications.

Volar wrist ganglion excision through the flexor carpi radialis sheath.

Volar wrist ganglions are much less frequent than their dorsal counterparts but provide much more surgical trepidation due to their proximity to the radial artery. With the majority arising from the radiocarpal joint, we have found that entering the flexor carpi radialis sheath and accessing the ganglion through the floor of the sheath allows for a relatively safe excision of these benign hand tumors.

Methylene blue-enhanced arthroscopic resection of dorsal wrist ganglions.

The ganglion is the most common soft tissue mass of the hand and wrist. Over the past 10 to 15 years, there has been a growing interest in arthroscopic treatment of dorsal wrist ganglions. Proposed advantages of arthroscopy include greater motion (particularly wrist flexion), improved cosmesis, and potential to identify/treat other intra-articular pathology. Despite the documented clinical success of arthroscopic ganglion excision, limitations include inconsistent identification of the ganglion stalk. Our described technique offers a means by which to improve visualization of the ganglion stalk intra-articularly to produce a more effective and efficient arthroscopic ganglion excision. During the procedure, a small volume of methylene blue solution is injected into the cyst. Its communication with the joint is apparent arthroscopically, thus identifying the location of the stalk. With the ability to precisely identify the ganglion stalk using an injection of methylene blue, the surgeon can direct the arthroscopic debridement toward the appropriate pathologic tissue. Unnecessary debridement of uninvolved tissue can be avoided with the technique. This also allows for optimal portal placement and, in particular, indicates whether a midcarpal portal should be employed. This should result in fewer recurrences, decreased operative time, and less iatrogenic injury.

Arthroscopic technique for medial epicondylitis: technique and safety analysis.

PURPOSE: The goals of this study are to report on a novel arthroscopic technique for the treatment of medial epicondylitis and to further describe the anatomic relations between the site of arthroscopic debridement and both the ulnar nerve and medial collateral ligament (MCL) complex. METHODS: Arthroscopic debridement of the medial epicondyle was performed on 8 fresh-frozen cadaveric specimens. Each specimen was dissected, and the shortest distance from the debridement site to both the ulnar nerve and MCL complex was measured with a 3-dimensional motion-tracking system. RESULTS: The mean distance between the debridement site and the ulnar nerve was 20.8 mm (range, 14.4 to 25.1 mm), and the mean distance between the medial debridement site and the origin of the anterior bundle of the MCL was 8.3 mm (range, 5.9 to 10.4 mm). CONCLUSIONS: Our results suggest that arthroscopic debridement of the medial epicondyle can be performed with low risk of injury to the ulnar nerve or MCL complex. CLINICAL RELEVANCE: This cadaveric study indicates a potential role for elbow arthroscopy in the surgical management of refractory medial epicondylitis.

Arthroscopic treatment of lateral epicondylitis.

Lateral epicondylitis refractory to conservative care can be effectively treated by arthroscopic release of the extensor carpi radialis brevis origin. Advantages to the technique include the ability to address other intra-articular sources of pain (capsular tears, radiocapitellar plica, etc.), a potentially faster return to work and sports, and a smaller incision. This article provides step-by-step descriptions and illustrations of the surgical technique.

Carpal growth and function after pediatric transcarpal hand replant: case report.

This case discusses the technique, postoperative course, and functional outcomes 5 years after an amputation between the cartilaginous anlages of the growing carpus in a 7-year-old boy. The lunate remained attached to the arm, whereas the scaphoid and the remainder of the carpus were contained within the amputated part. After 5 years, the patient had 94% growth compared to the other side, a Minnesota dexterity test in the 75th percentile, 0/10 pain, near-normal sensation, grip strength 17% of the other side, and lateral pinch 79% of the other side.

Management of lateral epicondylitis: current concepts.

Lateral epicondylitis, or tennis elbow, is a common cause of elbow pain in the general population. Traditionally, lateral epicondylitis has been attributed to degeneration of the extensor carpi radialis brevis origin, although the underlying collateral ligamentous complex and joint capsule also have been implicated. Nonsurgical treatment, the mainstay of management, involves a myriad of options, including rest, nonsteroidal anti-inflammatory drugs, physical therapy, cortisone, blood and botulinum toxin injections, supportive forearm bracing, and local modalities. For patients with recalcitrant disease, the traditional open débridement technique has been modified by multiple surgeons, with others relying on arthroscopic or even percutaneous procedures. Without a standard protocol (nonsurgical or surgical), surgeons need to keep abreast of established and evolving treatment options to effectively treat patients with lateral epicondylitis.

Thumb carpometacarpal arthroscopy: a topographic, anatomic study of the thenar portal.

Arthroscopic treatment of osteoarthritis of the thumb carpometacarpal joint has been well described; however, the current site of the 2 working portals, especially the 1-R portal, may be complicated by neurovascular morbidity. This is owing to the close proximity of these portals to important nerves and vessels surrounding the carpometacarpal joint. We studied 7 cadaveric wrists to map out the topographic, anatomic, and arthroscopic position of a new thenar portal. We hypothesized that it would increase considerably the safe zone distances of the portal from vital structures of the joint compared with the traditional portals. This study showed that the thenar portal increases considerably the safe zone of the portal from the sensory branches of the radial nerve and the radial artery and does not put the motor branch of the median nerve at risk. In addition the thenar portal allows for better visualization of the carpometacarpal joint, which leads to improved ability to perform arthroscopic trapeziectomy.

Three-dimensional in vivo kinematics of the distal radioulnar joint in malunited distal radius fractures.

How malunion of the distal radius affects the kinematics of the distal radioulnar joint in vivo was evaluated. A novel computed tomography image-based technique was used to quantify radioulnar motion in both wrists of 9 patients who had unilateral malunited distal radius fractures. In the injured wrists dorsal angulation averaged 21 degrees +/- 6 degrees, radial inclination averaged 18 degrees +/- 5 degrees, and radial shortening averaged 21 +/- 3 mm. Clinically, the average range of motion of the injured wrists was 75 degrees +/- 25 degrees pronation and 73 degrees +/- 23 degrees supination. Kinematics of the radius during pronation and supination in the malunited forearms was indistinguishable from that in the uninjured forearms. In both the axis of rotation of the radius passed through the center of the ulnar head, although it shifted slightly ulnar and volar in supination and radial and dorsal during pronation. In contrast to previous in vitro biomechanical findings, there was no dorsovolar radial translation at the extremes of pronation or supination and no translation of the radius along the rotation axis. Soft tissues may play a larger role in limiting function than previously appreciated, and treatment may require correction of altered soft tissue structures as well as any abnormal bone anatomy.