Coronal Fracture of the Lunate in Advanced Kienböck Disease: Reestablishing Midcarpal Congruency to Enable Osteochondral Reconstruction: A Case Report

Medial Femoral Trochlea Osteochondral Flap Reconstruction of the Previously Unsalvageable Kienbock-Associated Lunate With a Coronal Split

PURPOSE

Patients with Kienbock disease can present with coronal fracture and collapse of the proximal lunate (Unified B2/Bain grade 1, 2B). Traditionally, this was considered unsalvageable. However, medial femoral trochlea (MFT) osteochondral reconstruction, used to recreate the proximal lunate surface, can be paired with reduction and repair of the coronal plane fracture, thus restoring midcarpal congruity. The purpose of this study was to report radiographic and clinical outcomes following lunate coronal fracture fixation at the time of MFT osteochondral reconstruction.

METHODS

This was a retrospective study performed at a single institution. We identified patients with Kienbock disease who underwent MFT osteochondral reconstruction from 2014 to 2023. Patients were included if they had a coronal fracture of the lunate distal articular surface fixed at the time of surgery. Radiographic and clinical parameters were evaluated, including carpal height ratio, union rate, presence of heterotopic ossification, need for revision surgery, and patient-reported outcome measures.

RESULTS

Thirty-three patients were included, with a mean age of 27.5 years (range: 15-41); 19 (58%) were women. Mean radiographic follow-up time was 5.8 months, and mean clinical follow-up time was 22.6 months. Union was achieved in 30/33 patients (91%). Carpal height ratio improved from 1.32 to 1.4. Two patients (6%) required reoperation, one for removal of heterotopic ossification and another for conversion to proximal row carpectomy. Patients demonstrated meaningful improvement in brief Michigan Hand Questionnaire and Patient-Reported Outcomes Measurement Information Upper Extremity scores. Range of motion before and after surgery was similar.

CONCLUSIONS

Lunate coronal fracture fixation with MFT osteochondral reconstruction represents an additional management option in select patients with Kienbock disease. This technique restores the midcarpal joint during lunate reconstruction and may allow patients to avoid salvage procedures. Early radiographic and clinical outcomes are promising.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Lunate Fracture Morphology in Kienbock's Disease-A Computed Tomography Study

Background  The pathogenesis of Kienbock's disease is poorly understood. The coronal fracture line is acknowledged as a poor prognostic marker in the disease. Other fracture types in the Kienbock's wrist have subsequently been identified. Questions/Purposes  The aim is to study the fracture morphology of the lunate in a cohort of patients using computed tomography. Methods  Patient images were acquired using a set protocol with four-dimensional computed tomography scanning. Images were reviewed by two orthopaedic surgeons and a consultant radiologist. Static and dynamic images were assessed and a fracture map created. The relationship of fracture type to other parameters was then analyzed. Results  Twenty-three patients were included in the study, including 11 males and 12 females, with a mean age of 43 years. Total frequency of fracture lines in the cohort was coronal - 26, proximal subchondral bone plate type - 24, avulsion - 19, sagittal - 16, and distal subchondral bone plate type - 11. There were statistically significantly more proximal than distal subchondral bone plate fractures ( p  = 0.03), and more coronal fractures than distal subchondral bone plate fractures ( p  = 0.01). There were statistically significantly more radiolunate ligament-avulsion types ( p <0.001) than other types. The sagittal fracture line through the lunate approximated closely to the ulnar edge of the capitate and the ulnar edge of the radius. Conclusion  Study on the fracture morphology in the Kienbock's wrist has improved our understanding of the disease pathogenesis. Fracture lines may correspond to loading points, intrinsic and extrinsic ligament avulsions. These fracture types may play a role in disease progression and are important to identify when considering lunate salvage surgery.

An Algorithmic Approach to the Treatment of Kienböck Disease

The algorithm and rationale described is a reflection of our own surgical experience for this challenging disorder and can be compared with other publications. Our algorithm has evolved from treatment of a large volume of patients with Kienböck disease in a referral practice. However, it is limited to the management that we have found logical, effective, and within our scope of experience. The treatment guidelines for our specialty as a whole will evolve as our understanding of the etiology and our ability to quantify efficacy improves.

Medial femoral trochlea flap reconstruction versus proximal row carpectomy for Kienböck's disease: a morphometric comparison

Surgical options for advanced Kienböck's disease include proximal row carpectomy or lunate reconstruction with a medial femoral trochlea osteochondral flap. This study compares morphology of the proximal capitate and the medial femoral trochlear surfaces to the proximal lunate using three-dimensional geometric morphometric analysis. Virtual articular surfaces were extracted from MRI studies of ten healthy volunteers. Distances between corresponding points on the proximal lunate and proximal capitate or medial femoral trochlear surfaces were measured. In seven subjects, mean inter-surface distance for the medial femoral trochlea-proximal lunate pair was significantly lower than the proximal capitate-proximal lunate pairing. In three subjects, mean proximal capitate-proximal lunate distance was significantly lower. We conclude that the medial femoral trochlear flap was anatomically closer to the shape of the proximal lunate in the majority of the examined subjects. However, we found that in three out of ten cases, the proximal capitate was a better match.

The free vascularized lateral femoral trochlea osteochondral graft: a reliable alternative for Stage III Kienböck's disease

Lunate reconstruction using a lateral femoral trochlea osteochondral graft was carried out in 27 patients with Stage III Kienböck's disease from 2012 to 2019. Twenty-three of these patients could be followed-up in this retrospective study. Ten were women and 13 men. Nine were Lichtman Stage IIIA, seven Stage IIIB and seven Stage IIIC. The mean follow-up was 39 months (range 12-86). Bony consolidation was found in 18 of the 23 patients, with no graft loss. The mean Disabilities of the Arm, Shoulder and Hand score (DASH score) was 11 and the Modified Mayo Wrist Score was 83. There were only two radiological deteriorations, with the same or improved Lichtman classifications in the other patients and a significant reduction in pain. Postoperative extension of the wrist (52°) and flexion (48°) were comparable with preoperative values and, respectively, 81% and 72% of the contralateral side. Grip strength and pinch grip were 32 kg and 12 kg, 88% and 94% of the other hand, respectively, and an insignificant increase compared with the preoperative values. The vascularized lateral femoral trochlea osteochondral graft yields good short- and mid-term results in Grade III Kienböck's disease.Level of evidence: IV.

Preliminary Clinical, Radiographic, and Patient-Reported Outcomes of the Medial Femoral Trochlea Osteochondral Free Flap for Lunate Reconstruction in Advanced Kienböck Disease

PURPOSE

We aimed to describe the radiographic, functional, and patient-reported outcomes (PROs) of medial femoral trochlea osteochondral free flap reconstruction of the proximal lunate in stage IIIA and IIIB Kienböck disease.

METHODS

Eighteen adult patients underwent medial femoral trochlea reconstruction of the proximal lunate for advanced Kienböck disease by a single surgeon. Eight of these patients returned for clinical examination, radiographs, and completion of PRO questionnaires. An additional 4 patients completed PRO questionnaires remotely.

RESULTS

The mean patient age was 28.4 years. The mean radiographic and physical examination follow-up was 1.4 and 2.2 years, respectively. The mean PRO follow-up was 2.1 years. Radiographic measurements (carpal height ratio, radioscaphoid angle) demonstrated that carpal collapse was halted, and carpal alignment was maintained, after surgery. Wrist flexion (38.3°) and extension (37.3°) were unchanged by this operation, and postoperative pinch and grip strength were 90% and 68% of the uninjured side, respectively. The mean postoperative Disabilities of the Arm, Shoulder, and Hand score was 10.8, and the Patient-Rated Wrist Evaluation score was 18.1. Knee Injury and Osteoarthritis Outcomes Score subscales, International Knee Documentation Committee, and Kujala lower extremity PRO scores ranged from 83.1 to 96.8. The Patient-Reported Outcomes Measurement Information System Global Health, Physical Function, Pain Intensity, Pain Interference, and Pain Behavior scores reflected good postoperative patient health and function and low pain levels.

CONCLUSIONS

Following medial femoral trochlea reconstruction of the proximal lunate for advanced Kienböck disease, we observed a cessation of radiocarpal collapse. After surgery, patients demonstrated acceptable levels of function, pain, and wrist range of motion.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic V.