Operative correction of swan-neck and boutonniere deformities in the rheumatoid hand

Dorsal capsule release and lateral band translocation for a stiff swan neck deformity without articular involvement

BACKGROUND

The treatment for proximal interphalangeal joint (PIP) stiffness in extension requires extensor tenolysis, concomitant procedures to restore flexion, and intensive therapy. A stiff swan neck deformity without articular involvement is rare and the treatment is always challenging.

METHODS

Six patients with stiff swan neck deformities were operated between 2016 and 2023, and the outcome was analyzed retrospectively. A dorsal capsule release and radial lateral band translocation volar to the PIP joint axis were done. This translocation was maintained by a sling formed by the flexor digitorum superficialis and the free margins of the accessory collateral ligament. The range of movements in the PIP joint, visual analog scale (VAS), and functional outcomes were analyzed by the Michigan Hand Outcome Questionnaire (MHOQ) score.

RESULTS

The mean follow-up was 49.5 months (range 48-52 months). The mean preoperative PIP joint extension was 8 (range 5-10) degrees of extension), and the mean preoperative PIP joint flexion was 0. All patients improved after the surgery and the mean flexion of the PIP joint at follow-up was 95 degrees; extension was 1 degree (range 0-5 degrees). The mean Michigan Hand Outcomes Questionnaire (MHOQ) score was 92 (range 90-95) and the VAS was 0.

CONCLUSIONS

Dorsal capsule contracture release and lateral band translocation to the volar axis of the PIP joint seem to be the possibilities for correcting stiff swan neck deformity.

LEVEL OF EVIDENCE

IV, retrospective case study.

Effect of a Flexor Digitorum Superficialis Hemitenodesis on Reducing Volar Plate Strains for Swan Neck Deformities

BACKGROUND

Flexor digitorum superficialis (FDS) hemitenodesis is a common procedure to treat swan neck deformity (SND). We hypothesize that this surgical technique is a biomechanically effective way to reduce strain in the volar plate at the proximal interphalangeal joint (PIPJ).

METHODS

Fifteen digits from 5 cadaveric specimens were tested using a novel in vitro active finger motion simulator under 4 finger conditions: intact, SND, FDS hemitenodesis, and FDS hemitenodesis with distal interphalangeal (DIP) joint fusion. Tensile loads in FDS and flexor digitorum profundus (FDP) and joint ranges of motion were measured by electromagnetic tracking. In addition, strain gauges were inserted under the volar plate to measure strain during PIPJ hyperextension. Results were analyzed using 1-way repeated-measures analysis of variance tests.

RESULTS

The SND condition increased volar plate strain by 176% ± 25% (P < .001) compared with the intact condition. The FDS hemitenodesis repair relieved more than 50% of the SND strain, restoring it to within no statistical difference from intact. The DIP fusion further reduced strain with no further statistical significance. At full flexion, FDS and FDP tendon loads diverged as a function of the test condition (P < .001). With the FDS hemitenodesis, the FDP load increased by 2.1 ± 1.5 N from the SND condition (P < .001), whereas the FDS load decreased by 1.3 ± 1.3 N (P = .012).

CONCLUSION

The FDS hemitenodesis repair restored strains to within 3.0 milli-strain of the intact condition with no significant difference. Application of DIP fusion did not further protect the PIPJ from increased hyperextension and further exacerbated the imbalance of flexor tendon loads.

Treating the Proximal Interphalangeal Joint in Swan Neck and Boutonniere Deformities

Swan neck and boutonniere deformities of the proximal interphalangeal (PIP) joint are challenging to treat. In a swan neck deformity, the PIP joint is hyperextended with flexion at the distal interphalangeal (DIP) joint. In a boutonniere deformity, there is flexion the PIP joint with hyperextension of the DIP joint. When the deformities are flexible, treatment begins with splinting. However, when the deformity is fixed, serial casting or surgery is often necessary to restore joint motion before surgical correction. Many surgical techniques have been described to treat both conditions. Unfortunately, incomplete correction and deformity recurrence are common.

Complications of Proximal Interphalangeal Joint Injuries: Prevention and Treatment

Proximal interphalangeal joint injuries are one of the most common injuries of the hand. The severity of injury can vary from a minor sprain to a complex intra-articular fracture. Because of the complex anatomy of the joint, complications may occur even after an appropriate treatment. This article provides a comprehensive review on existing techniques to manage complications and imparts practical points to help prevent further complications after proximal interphalangeal joint injury.

Swan Neck Deformity Mimicking Claw Hand Caused by Arthritis in Leprosy

Swan neck deformity is a hyperextension of the proximal interphalangeal (PIP) joints and flexion of the distal interphalangeal (DIP) joints. Claw hand is a hyperextension of the metacarpal joints and flexion of the PIP joints, accompanied by reduced motor strength. A 23-year-old female, who was released from leprosy treatment, presented with a bend of the second to fifth fingers of both hands. There was hyperextension of the PIP joints and flexion of the DIP joints from the second to fifth fingers of both hands, thickening of the ulnar nerves, and hypoesthesia without motor impairment of the fourth and fifth fingers of both hands. Radiograph examination revealed cupping of the base of the proximal phalangeal joints of the second, third, and fifth fingers of the left hand and of the second and fifth fingers of the right hand. Additionally, narrowing of the metacarpophalangeal joints of the second, third, and fifth fingers of the right hand and sclerosis of the second and fifth fingers of the right hand were also observed. Claw hand is frequently reported in leprosy, while swan neck deformity is frequently reported in rheumatoid arthritis. To our knowledge, this is the first reported case with swan neck deformity caused by arthritis in leprosy.

Superficialis Sling (Flexor Digitorum Superficialis Tenodesis) for Swan Neck Reconstruction

Swan neck deformity, or hyperextension of the proximal interphalangeal joint, may occur secondary to trauma, rheumatoid arthritis, cerebral palsy, or Ehlers-Danlos syndrome, and can be treated with tenodesis of one slip of the flexor digitorum sublimis tendon. This technique has several variations, differing primarily in the specific location and method that a single slip of the flexor digitorum sublimis tendon is secured, but they all serve to create a static volar restraint against hyperextension. Options include tunneling the tendon through the bone of the proximal phalanx, attaching the tendon to the A1 or A2 pulley, or securing the tendon with bone anchors in the proximal phalanx.

Applying evidence in the care of patients with rheumatoid hand and wrist deformities

The traditional approach in managing rheumatoid hand deformities is based on the individual surgeon's experiences. In the current era of evidence-based medicine, formulating treatment for the rheumatoid hand fits perfectly within the framework of evidence-based medicine by leveraging the best evidence from the literature, incorporating surgeons' experience and considering patients' preferences. In this Special Topic article, we use a case example to illustrate how evidence-based medicine can be practiced within the framework of treating rheumatoid hand deformities by distilling the best evidence from the literature to guide surgeons in a rational approach for treating this common condition.

Intrinsic contracture of the hand: diagnosis and management

Intrinsic contracture of the hand may result from trauma, spasticity, ischemia, rheumatologic disorders, or iatrogenic causes. In severe cases, the hand assumes a posture with hyperflexed metacarpophalangeal joints and hyperextended proximal interphalangeal joints as the contracted interossei and lumbrical muscles deform the natural cascade of the fingers. Considerable disability may result because weakness in grip strength, difficulty with grasping larger objects, and troubles with maintenance of hygiene commonly encumber patients. Generally, the diagnosis is made via history and physical examination, but adjunctive imaging, rheumatologic testing, and electromyography may aid in determining the underlying cause or assessing the severity. Nonsurgical management may be appropriate in mild cases and consists of occupational therapy, orthoses, and botulinum toxin injections. The options for surgical management are diverse and dictated by the cause and severity of contracture.

Hand therapy for dysfunction of the intrinsic muscles

Intrinsic muscle dysfunction can be devastating. Patients often have difficulty using the affected hand for most daily activities. Physicians, occupational therapists, and patients have to work together to enable the patient to regain functional use of the hand to perform activities that are a part of their life roles. Occupational therapists play an important role in the rehabilitation process to regain motion, strength, and dexterity so that patients can use the hand more functionally. Patient education and active participation in their therapy is also essential in the functional recovery of the hand.

Reconstruction of the rheumatoid hand

Previous studies have shown large variation in the rate of common surgical procedures performed for the rheumatoid hand. This article provides a comprehensive overview of each surgical treatment option for rheumatoid hand reconstruction.

Treatment of boutonniere finger deformity in rheumatoid arthritis

Boutonniere finger deformities occur frequently in patients with rheumatoid arthritis. The deformity consists of flexion of the proximal interphalangeal joint and hyperextension of the distal interphalangeal joint. Treatment decisions are based on the degree of joint deformity, joint motion, passive joint correctability, and the status of the articular surface. Treatment options can then be based on the classification of the deformity; options consist of corrective splinting, injections, synovectomy, terminal tenotomy, extensor reconstruction, or salvage surgery (arthrodesis or arthroplasty).

The role of tenodesis in surgery of the upper limb

This paper describes the presence of tenodesis effects in normal physiology and explores the uses of operative tenodesis in surgery of the upper limb.

Reconstruction of digital deformities in rheumatoid arthritis

Digital deformities result from rheumatoid synovitis. These deformities are easier to treat in the early stage, when the deformity is passively correctable. Treatment options become limited as the disease progresses and the deformity becomes fixed. Surgical treatment of digital deformities is last in the priority of surgical procedures for the rheumatoid hand and wrist. It is therefore important to understand the patient's needs and expectations for improvement and attempt to match them with the surgical options that can predictably improve the patient's function. A close collaboration with the patient's rheumatologist is helpful in the overall management of patients.

Kinematic evaluation of the finger's interphalangeal joints coupling mechanism--variability, flexion-extension differences, triggers, locking swanneck deformities, anthropometric correlations

The human finger contains tendon/ligament mechanisms essential for proper control. One mechanism couples the movements of the interphalangeal joints when the (unloaded) finger is flexed with active deep flexor. This study's aim was to accurately determine in a large finger sample the kinematics and variability of the coupled interphalangeal joint motions, for potential clinical and finger model validation applications. The data could also be applied to humanoid robotic hands. Sixty-eight fingers were measured in seventeen hands in nine subjects. Fingers exhibited great joint mobility variability, with passive proximal interphalangeal hyperextension ranging from zero to almost fifty degrees. Increased measurement accuracy was obtained by using marker frames to amplify finger segment motions. Gravitational forces on the marker frames were not found to invalidate measurements. The recorded interphalangeal joint trajectories were highly consistent, demonstrating the underlying coupling mechanism. The increased accuracy and large sample size allowed for evaluation of detailed trajectory variability, systematic differences between flexion and extension trajectories, and three trigger types, distinct from flexor tendon triggers, involving initial flexion deficits in either proximal or distal interphalangeal joint. The experimental methods, data and analysis should advance insight into normal and pathological finger biomechanics (e.g., swanneck deformities), and could help improve clinical differential diagnostics of trigger finger causes. The marker frame measuring method may be useful to quantify interphalangeal joints trajectories in surgical/rehabilitative outcome studies. The data as a whole provide the most comprehensive collection of interphalangeal joint trajectories for clinical reference and model validation known to us to date.

Effectiveness of two finger splints for swan neck deformity in patients with rheumatoid arthritis: a randomized, crossover trial

OBJECTIVE

To compare the effectiveness and acceptability of silver ring splints (SRS) and commercial prefabricated thermoplastic splints (PTS) in treating swan neck deformities in patients with rheumatoid arthritis (RA).

METHODS

Consecutive patients with RA and a mobile swan neck deformity were included in a randomized, crossover trial. In 2 different sequences, patients used both splints for 4 weeks, with a washout period of 2 weeks. Afterward, patients used the preferred splint for another 12 weeks. The primary outcome measure was dexterity measured with the Sequential Occupational Dexterity Assessment (SODA). Secondary outcome measures included other measures of hand function, satisfaction with the splints, and splint preference.

RESULTS

Fifty patients were included, and 47 (94%) of those completed the study. Eighteen patients (36%) had 1 swan neck deformity, whereas the other patients had 2 or more. The improvement of the total SODA score with the SRS (11.2; 95% confidence interval [95% CI] 8.1, 14.3) and PTS (10.8; 95% CI 7.5, 14.1) was similar (difference -0.5; 95% CI -2.2, 1.2). In addition, there were no significant differences in change scores regarding the other clinical outcome measures, or satisfaction. Twenty-four patients preferred the SRS, 21 preferred the PTS, and 2 patients chose neither. A comparison in the 12-week followup period yielded similar clinical outcomes, with the exception of a significantly higher score in 3 items of satisfaction in the SRS group.

CONCLUSION

For patients with RA and a mobile swan neck deformity, SRS and PTS are equally effective and acceptable.

Correction of bilateral congenital swan-neck deformity by use of Mitek mini anchor: a new technique

Congenital swan neck deformity is a rare condition, secondary to congenital laxity of the palmar plate of the proximal interphalangeal joint. Here, we describe a new surgical method which is based on the palmar plate reinforcement using the Mitek mini anchor system (Mitek Surgical Products Inc., Norwood, MA, USA). Four fingers of a patient with congenital swan neck deformities were corrected with this technique at two stages. First, the anchor was inserted into the volar surface of the proximal phalanx. The two sutures of the anchor system were then crossed the PIP joint in a V fashion. Two holes, 5mm apart from each other, were created through the middle phalanx distal to both insertion points of superficial flexor tendon. The suture ends of the anchor were passed through these holes from the volar to the dorsal side of the middle phalanx and then turned around the edges of the bone to the volar surface. They were tied to each other as the PIP joint was stabilised at 20 degrees flexion by use of a K-wire. The K-wire was removed 21 days later and a rehabilitation program was then initiated. A second operation for the two fingers of the opposite hand was performed 2 months after the first operation. No postoperative complications were encountered. At 2 years follow-up, the active range of motion was within normal limits at PIP and DIP joints of all four fingers without any recurrence of hyperextension or hyperflexion. The final result was satisfactory regarding both the functional and cosmetic aspects. The Mitek mini anchor offers a practical, reliable and functional reconstruction of the volar plate in the management of congenital swan neck deformities. We believe that it may also be used for the acquired deformities.

Long-term assessment of Swanson implant arthroplasty in the proximal interphalangeal joint of the hand

PURPOSE

The purpose of this study was to evaluate the clinical results of Swanson silicone implant arthroplasty of the proximal interphalangeal (PIP) joint, specifically evaluating clinical results with long-term assessment.

METHODS

A retrospective review of 70 silicone implants of the PIP joint in 48 patients was performed with an average follow-up period of 6.5 years (range, 3-20 y). Clinical assessment included motion, stability, and alignment. Radiographic assessment included implant fracture, deformity, and cystic bone resorption. The pathology consisted of degenerative joint disease in 14, posttraumatic arthritis (TA) in 11, rheumatoid arthritis (RA) in 13, and idiopathic arthritis (IA) associated with collagen disease in 12 patients. Swan neck and boutonniere deformities were assessed separately. Statistical analysis of preoperative risk factors was compared with the postoperative assessment of pain, motion, and function (return to work).

RESULTS

There was no significant change in the active range of motion (ROM) before and after PIP arthroplasty (26 degrees vs 30 degrees ). Correction of swan neck and boutonniere deformities was difficult, usually leading to poor results. There was improvement in maximum active extension before surgery lacking 32 degrees to after surgery lacking 18 degrees . From a statistical standpoint rheumatoid joint involvement with PIP arthroplasty had poorer results than degenerative or posttraumatic arthritis with respect to pain relief and ROM. Pain relief was present in 70% of replaced PIP joints with residual pain and loss of strength in 30%. Radiographic analysis showed abnormal bone formation (cystic changes) in 45%. There were 11 implant fractures and 9 joints that required revision surgery.

CONCLUSIONS

Silicone replacement of the PIP joint is effective in providing relief of pain from arthritis but does not provide improvement in motion or correction of deformity. It provided a poorer outcome in rheumatoid disease in comparison with degenerative, posttraumatic, or idiopathic arthritis.