Computed tomography-based 3-dimensional preoperative planning for unlinked total elbow arthroplasty

HYPOTHESIS

Three-dimensional (3D) surgical planning for unlinked total elbow arthroplasty (TEA) would be helpful for estimation of the implant size and accurate placement of implants.

METHODS

We included 28 patients who underwent TEA with an unlinked total elbow implant in this study. All patients underwent computed tomography scans of the elbow before surgery, and a 3D digital model of the elbow was reconstructed. After the appropriate size and position of the prosthesis were determined, 10 points around the bone tunnel (4 on the humerus and 6 on the ulna) were measured to plan the insertion of the humeral and ulnar stems. Two-dimensional planning was also performed using anteroposterior and lateral radiographs. Intraoperatively, the surgeon measured the planned parameters using a slide gauge to reproduce the 3D planned position of the stem insertion.

RESULTS

The stem sizes were accurately estimated in 57% of patients for the humerus and 68% for the ulna with 2-dimensional planning and in 86% for the humerus and 96% for the ulna with 3D planning. The mean differences between the positions of the prostheses after surgery with reference to the planned positions were 0.8° of varus and 1.5° of flexion for the humeral component and 0.7° of varus and 2.9° of flexion for the ulnar component. We did not evaluate rotational positioning in this study.

CONCLUSIONS

The 3D surgical planning allowed accurate estimation of the implant size and appropriate placement of implants. This method may contribute to a reduced incidence of complications and improved long-term outcomes from TEA.

Temporary Sternoclavicular Stabilization Using an Innovative Blocking Technique with Kirschner Wires for the Treatment of Posterior Sternoclavicular Joint Injury in Adolescent Patients: A Report of Two Cases

CASE

A 15-year-old boy with a posterior physeal fracture-dislocation of the medial aspect of the clavicle and a 14-year-old boy with a posterior sternoclavicular joint dislocation were successfully treated with temporary sternoclavicular stabilization using an innovative blocking technique with Kirschner wires.

CONCLUSION

When treating posterior sternoclavicular joint injuries, posterior instability should be securely stabilized. Temporary blocking stabilization of the sternoclavicular joint using Kirschner wires does not rigidly fix the sternoclavicular joint, but it prevents posterior displacement of the proximal aspect of the clavicle. This stabilizing technique is a simple, safe, and viable treatment option for adolescent patients with a posterior sternoclavicular joint injury.

Costal Osteochondral Autograft for Advanced Osteochondritis Dissecans of the Humeral Capitellum in Adolescent and Young Adult Athletes: Clinical Outcomes with a Mean Follow-up of 4.8 Years

BACKGROUND

Costal osteochondral grafting is a technique to achieve anatomical and biological repair of articular defects. Some small series of clinical applications of this procedure for advanced osteochondritis dissecans of the humeral capitellum, with short-term follow-up, have been reported; however, longer-term outcomes remain unclear. The purpose of this study was to clarify longer-term clinical outcomes of costal osteochondral autografts in the treatment of advanced osteochondritis dissecans of the humeral capitellum.

METHODS

Seventy-two patients with an osteochondral defect of the humeral capitellum were treated with costal osteochondral autograft and followed for a minimum of 3 years (mean follow-up, 57 months; range, 36 to 147 months). The mean patient age was 14.3 years. Clinical outcomes, including elbow range of motion, Timmerman and Andrews clinical rating score, donor-site morbidity, responses to a questionnaire regarding a return to sporting activities, and radiographic findings, were evaluated.

RESULTS

The mean elbow range of extension/flexion increased significantly, from -21°/122° preoperatively to -4°/136° postoperatively (p < 0.001). The mean clinical rating score improved significantly, from 101 to 190 by the latest follow-up (p < 0.001). The overall clinical score-based assessment was excellent for 60 patients, good for 9, and fair for 3. Seventy of the 72 patients returned to their original sport. The remaining 2 patients had changed sporting activities before surgery and did not return to baseball, despite satisfactory clinical results.

CONCLUSIONS

Costal osteochondral autograft successfully achieved anatomical and biological reconstruction in the treatment of advanced osteochondritis dissecans of the humeral capitellum.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Evaluation of the Translation Distance of the Glenohumeral Joint and the Function of the Rotator Cuff on Its Translation: A Cadaveric Study

PURPOSE

To evaluate the distance and position of humeral head translation during glenohumeral motion and to investigate the function of the rotator cuff in glenohumeral translation.

METHODS

Using 9 cadavers, glenohumeral translation during passive pendulum motion was tracked by an optical motion capture system. Tension was applied to 5 compartments of the rotator cuff muscles, and 7 different conditions of rotator cuff dysfunction were sequentially simulated. Three-dimensional glenohumeral structure was reconstructed from the computed tomography images of the specimens, and the distance and position of glenohumeral translation were compared among the conditions.

RESULTS

The average radius of glenohumeral translation was 10.6 ± 4.3 mm when static loading was applied to all rotator cuff muscles. The radius increased significantly in the models without traction force on the supraspinatus and total subscapularis tendons (P = .030). The position of the translation center did not change in the mediolateral direction (P = .587) and in the anteroposterior direction (P = .138), but it moved significantly superiorly in the models without supraspinatus and infraspinatus loading (P = .011) and in those without supraspinatus, infraspinatus, and teres minor loading (P < .001).

CONCLUSIONS

The distance and position of humeral head translation during glenohumeral motion changed with rotator cuff deficiency. The present study indicated that the subscapularis plays an important role in maintaining the central position of the humeral head, and that the infraspinatus acts as a major depressor of the humeral head during shoulder motion.

CLINICAL RELEVANCE

The results of this study suggest that extension of a tear into the subscapularis should be avoided to maintain the centering function of the glenohumeral joint in cases with rotator cuff tear.

Chronic calcific periarthritis of the elbow treated by cimetidine administration: Five cases

Calcific periarthritis or calcific tendinitis occurs most frequently in the shoulder and rarely in the elbow. Cimetidine was previously reported to be effective for chronic calcific periarthritis of the shoulder. Here, we present five patients with chronic calcific periarthritis of the elbow treated by administration of cimetidine; there were six affected elbows in these five patients. Although all patients had been treated with nonsteroidal anti-inflammatory drugs for at least 3 months, their symptoms were not relieved. All patients took oral administration of cimetidine 400 mg daily. The pain was completely relieved in an average of 1.8 months after the administration of cimetidine, and the calcification of the elbow disappeared in an average of 5.1 months. During the follow-up period, there were no symptoms suggesting a recurrence. Although the detailed mechanism of action of cimetidine on periarticular calcifications remains to be understood, cimetidine appears to be a potential therapeutic agent for chronic calcific periarthritis.

Scapular Winging Caused by Combined Palsy of the Spinal Accessory Nerve and the Long Thoracic Nerve: A Case Report

CASE

A 37-year-old man with scapular winging, caused by combined palsy of the spinal accessory nerve and the long thoracic nerve, was successfully treated with a pectoralis major transfer to substitute for the serratus anterior muscle, and with levator scapulae and rhomboid muscle transfers to substitute for the trapezius muscle.

CONCLUSION

The serratus anterior paralysis was thought to have occurred secondary to traction of the long thoracic nerve by the unsupported scapula following the spinal accessory nerve palsy. Even with combined paralyses of the serratus anterior and trapezius muscles, combined muscle transfers that substitute for the paralyzed muscles can improve shoulder function.

Transcatheter arterial embolization of abnormal vessels as a treatment for lateral epicondylitis refractory to conservative treatment: a pilot study with a 2-year follow-up

BACKGROUND

Abnormal vessels and accompanying nerves are possible sources of pain with lateral epicondylitis. The purpose of this study was to describe the safety and efficacy of transcatheter arterial embolization (TAE) for lateral epicondylitis resistant to conservative treatment.

METHODS

This prospective study was conducted in 24 patients with lateral epicondylitis resistant to conservative treatments for more than 3 months, with a symptom duration longer than 6 months, and with moderate to severe pain who were treated with TAE between March 2013 and October 2014. Two patients were lost to follow-up, and the remaining 22 patients were followed up for 2 years after TAE.

RESULTS

Abnormal vessels were identified in all of the patients. No major adverse events were observed. The Quick Disabilities of the Arm, Shoulder and Hand scores at baseline significantly decreased at 1, 3, 6, and 24 months after treatment (50.8 vs 23.4, 8.3, 5.3, and 2.7, respectively; all P < .001). There was a statistically significant (P < .001) change from baseline to the last observed value in all of the clinical parameters, including visual analog scale pain score, Patient-Rated Tennis Elbow Evaluation score, and pain-free grip strength. Magnetic resonance images obtained 2 years after TAE showed an improvement in tendinosis and tear scores compared with baseline, and no patients showed bone marrow necrosis, obvious cartilage loss, or muscle atrophy.

CONCLUSION

TAE could be one possible treatment option for patients with lateral epicondylitis that fails to improve with conservative treatments.

Lateral Para-Olecranon Approach for the Treatment of Distal Humeral Fracture

PURPOSE

To assess the outcomes of the lateral para-olecranon triceps-splitting approach for the treatment of distal humeral fracture.

METHODS

Ten patients (3 males, 7 females) with a mean age of 59 years were retrospectively reviewed. There were 2 A2, 3 C1, and 5 C2 fractures according to the AO/ASIF classification. Types B3 and C3 fractures were excluded from this study because the olecranon osteotomy approach was indicated to visualize the anterior fragment. The triceps was split at the midline, and the anconeus muscle was incised from the proximal ulna. The lateral half of the triceps along with anconeus was retracted laterally as a single unit. The distal part of the humerus could be visualized from medial and lateral windows by retracting the medial half of the triceps. The articular fragment was anatomically reduced and fixed temporarily with a Kirschner wire, and the reconstructed distal articular block was then fixed to the humeral shaft with double locking plates.

RESULTS

After surgery, average elbow flexion was 127° (range, 110°-145°), and extension was -10° (range, -20°-0°) at the average follow-up time of 12.4 months (range, 8‒20 months). Seven patients had normal muscle strength against full resistance (manual muscle testing grade 5), and the other 3 patients had slightly reduced muscle strength (grade 4). No articular stepoffs of more than 1 mm were seen on postoperative radiographs. There were no cases of triceps insufficiency and nonunion. The average (± SD) Mayo Elbow Score was 93.5 ± 5.8 points at the final follow-up.

CONCLUSIONS

The lateral para-olecranon approach is useful for the management of selected fractures of the distal humerus, preserving extension strength and providing satisfactory clinical outcomes, with no risk of olecranon osteotomy-related complications.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.

Inhibition of PDGFR signaling prevents muscular fatty infiltration after rotator cuff tear in mice

Fatty infiltration in muscle is often observed in patients with sizable rotator cuff tear (RCT) and is thought to be an irreversible event that significantly compromises muscle plasticity and contraction strength. These changes in the mechanical properties of the affected muscle render surgical repair of RCT highly formidable. Therefore, it is important to learn more about the pathology of fatty infiltration to prevent this undesired condition. In the present study, we aimed to generate a mouse model that can reliably recapitulate some of the important characteristics of muscular fatty infiltration after RCT in humans. We found that fatty infiltration can be efficiently induced by a combination of the following procedures: denervation of the suprascapular nerve, transection of the rotator cuff tendon, and resection of the humeral head. Using this model, we found that platelet-derived growth factor receptor-α (PDGFRα)-positive mesenchymal stem cells are induced after this intervention and that inhibition of PDGFR signaling by imatinib treatment can significantly suppress fatty infiltration. Taken together, the present study presents a reliable fatty infiltration mouse model and suggests a key role for PDGFRα-positive mesenchymal stem cells in the process of fatty infiltration after RCT in humans.

In-vitro identification of shoulder joint and muscle dynamics based on motion capture and musculoskeletal computation

Dynamics properties of shoulder joint and muscle are experimentally identified under different musculoskeletal conditions for a digital human model with accurate dynamics. Passive swing motions of scapula and upper limb bones in cadaveric specimen with and without muscles are measured by an optical motion capture system. External forces that are applied to the scapula bone are simultaneously measured by a force plate. The dynamics identification process consists of 3 steps: 1) identify the inertial parameters of the cadaveric specimen with and without muscles respectively, 2) identify the viscosity of the glenohumeral joint from the specimen without muscles, and 3) identify the viscosity of the shoulder muscles from the specimen with muscles and the identified joint viscosity. These parameters are identified in six cadaveric specimens. Their joint viscosities are 5.33E-02 ± 1.33E-02 Nms/rad (without muscles) and 1.07E-01 ± 2.28E-02 Nms/rad (with muscle), and their muscle viscosities are 6.69E+02 ± 8.11E+02 Ns/m (mean ± SD). The identified joint viscosity corresponds with the literature value. This measurement and identification algorithm would improve the dynamics of the digital human model and realize the accurate muscle activity estimation and the motion simulation.

Modified Extensor Pollicis Longus Rerouting Technique for Boutonniere Deformity of the Thumb in Rheumatoid Arthritis

PURPOSE

To assess the outcomes of a modified extensor pollicis longus (EPL) rerouting technique for boutonniere deformity of the thumb in patients with rheumatoid arthritis.

METHODS

A total of 21 thumbs in 18 patients with a mean age of 63 years were retrospectively analyzed after an average follow-up period of 3.2 years. The preoperative deformities were classified as either mild (5 thumbs) or moderate (16 thumbs). After either metacarpophalangeal (MCP) joint synovectomy or implant arthroplasty, the ulnarly dislocated EPL tendon was reduced dorsally and sutured to the dorsal base of the proximal phalanx. If the interphalangeal (IP) joint extended with manual traction on the proximal portion of the extensor pollicis brevis tendon, no further treatment was considered. If the IP joint did not extend with this maneuver, the insertion of the extensor pollicis brevis tendon was dissected and transferred to the distal portion of the EPL tendon.

RESULTS

The average MCP joint extensor lag improved from 62° (range, 32° to 85°) before surgery to 17° (range, active extension 12° to extensor lag 70°) at the final follow-up (P < .05), whereas average MCP joint flexion decreased from 83° (range, 52° to 95°) to 68° (range, 30° to 90°) (P < .05). Hyperextension at the IP joint was improved from 30° (range, 10° to 50°) before surgery to an average extensor lag of 2° (range, extensor lag 24° to hyperextension 20°) at the final follow-up. The average combined MCP and IP motion did not significantly change. The boutonniere deformity was improved in 18 of 21 thumbs. The 3 failures all had moderate-stage deformity prior to treatment.

CONCLUSIONS

A modified EPL rerouting technique provided satisfactory results together with a low risk of IP joint extension loss.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Osteochondritis dissecans on the medial aspect of the humeral head

The case of a 29-year-old man who had osteochondritis dissecans on the medial aspect of the humeral head is reported. Repetitive micro-trauma at a low elevated arm position was thought to have induced the osteochondral lesion.

Subcutaneous flexor tendon rupture in patients with rheumatoid arthritis

OBJECTIVE

We examined the clinical features and functional outcomes of surgically repaired subcutaneous flexor tendon ruptures in patients with rheumatoid arthritis (RA).

METHODS

This retrospective study included 41 fingers of 24 RA patients who underwent surgical treatment for flexor tendon ruptures. Evaluations performed at the time of presentation following rupture were C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), and disease activity score in 28 joints (DAS28)-ESR, as well as Larsen grading for carpal bone destruction. The ruptured tendon and postoperative active range of motion (ROM) of digits were also examined.

RESULTS

The mean CRP was 2.4 mg/dl, ESR was 52 mm/h, and the DAS28-ESR was 4.5. Carpal bone destruction according to Larsen grade IV-V was observed in 18/24 patients. Affected digits were most commonly the thumb (12) and the ring and little fingers (9 each). Tendon ruptures were most common in the carpal tunnel in zone IV. The mean postoperative finger ROM (flexion/extension) was 38°/2° for the interphalangeal (IP) joint of the thumb and 23°/-2° for the distal interphalangeal joint of the other four fingers.

CONCLUSIONS

Patients with flexor tendon ruptures present with high disease activity and advanced bone destruction. It is important to reduce the risk of progressive bone destruction and subsequent tendon rupture via tight control of disease activity.

Generation and characterization of a novel shoulder contracture mouse model

Frozen shoulder is a relatively common disorder that leads to severe pain and stiffness in the shoulder joint. Although this disorder is self-limiting in nature, the symptoms often persist for years, resulting in severe disability. Recent studies using human specimens and animal models have shown distinct changes in the gene expression patterns in frozen shoulder tissue, indicating that novel therapeutic intervention could be achieved by controlling the genes that are potentially involved in the development of frozen shoulder. To achieve this goal, it is imperative to develop a reliable animal joint contracture model in which gene expression can be manipulated by gene targeting and transgenic technologies. Here, we describe a novel shoulder contracture mouse model. We found that this model mimics the clinical presentation of human frozen shoulder and recapitulates the changes in the gene expression pattern and the histology of frozen shoulder and joint contracture in humans and other larger animal models. The model is highly reproducible, without any major complications. Therefore, the present model may serve as a useful tool for investigating frozen shoulder etiology and for identifying its potential target genes.

Lipoma in the subscapularis muscle causing scapular malposition

A 70-year-old woman had pain and fatigability of her left shoulder with asymmetric scapular position. The medial border of the scapula was more prominent in the left side compared to the right scapula, and scapular motion was different between sides. Magnetic resonance imaging showed a mass on the ventral surface of the scapula. Tumour resection was performed through the medial approach, and the tissue samples were found to be a lipoma with a pathological examination. Post-operatively, her pain immediately disappeared. Two years after surgery, no recurrence of the tumour had been found. Soft tissue tumours have never been reported as a cause of scapular malposition or winging. We reported a case with scapular malposition and dyskinesis caused by lipoma in the subscapularis muscle. Surgical resection successfully relieved her symptoms and improved the scapular motion. Soft tissue tumour occurring in the subscapularis muscle could possibly cause abnormal scapular position and motion.

Comparison of surgical treatments for triple extensor tendon ruptures in rheumatoid hands: A retrospective study of 48 cases

OBJECTIVE

This retrospective study was designed to evaluate the outcomes of four different surgical reconstructions for extensor tendon ruptures in ulnar three fingers in 48 patients with rheumatoid arthritis.

METHODS

The following four techniques were performed; palmaris longus tendon grafting (PL group; n = 9), extensor indicis proprius (EIP) tendon transfers (EIP group; n = 8), end-to-side transfers with tension-reduced early mobilization (End-to-side group; n = 16), and a combination of end-to-side and EIP transfers (Combination group; n = 15). Loss of extension was evaluated to determine the mean postoperative range of motion of the metacarpophalangeal (MP) joint and clinical outcomes were categorized using modified Geldmacher criteria.

RESULTS

Combination group demonstrated the best mean MP joint extension (-3°), followed by End-to-side group (-12°), EIP group (-16°), and PL group (-21°). Combination group yielded the best clinical outcomes with all cases showing good results.

CONCLUSIONS

The combination of end-to-side and EIP transfer was an effective surgical reconstruction procedure for triple fingers extension loss.

Anterior Transverse Divergent Dislocation of the Elbow in a Child: A Case Report

CASE

A five-year-old boy injured his right elbow. Radiography revealed an anterior dislocation of the elbow with an olecranon fracture and a proximal radioulnar joint dissociation. Computed tomography (CT) confirmed the disruption of the proximal radioulnar joint, and a diagnosis of anterior transverse divergent dislocation of the elbow was established. Open reduction and fixation of the ulna was performed with good clinical results.

CONCLUSION

We document a rare type of anterior divergent dislocation of the elbow. It is important to use CT to evaluate a proximal radioulnar joint dissociation to determine the correct diagnosis to aid in surgical planning.