Scapho-luno-capitate fusion with proximal lunate articular surface preservation for management of grade IIIA Kienböck's disease: a prospective case series.

BACKGROUND: Kienböck's disease is idiopathic lunate avascular necrosis, which may lead to lunate collapse, abnormal carpal motion and wrist arthritis. The current study aimed to assess the outcomes of treating stage IIIA Kienböck's disease by a novel technique of limited carpal fusion via partial lunate excision with preservation of the proximal lunate surface and scapho-luno-capitate (SLC) fusion. MATERIALS AND METHODS: We conducted a prospective study of patients with grade IIIA Kienböck's disease managed with a novel technique of limited carpal fusion comprising SLC fusion with preservation of the proximal lunate articular cartilage. Autologous iliac crest bone grafting and K-wires fixation were used to enhance the osteosynthesis of the SLC fusion. The minimum follow-up period was 1 year. A visual analog scale (VAS) and the Mayo Wrist Score were utilized for the evaluation of patient residual pain and functional assessment, respectively. A digital Smedley dynamometer was used to measure the grip strength. The modified carpal height ratio (MCHR) was used for monitoring carpal collapse. The radioscaphoid angle, scapholunate angle, and the modified carpal-ulnar distance ratio were used for the assessment of carpal bones alignment and ulnar translocation of carpal bones. RESULTS: This study included 20 patients with a mean age of 27.9 ± 5.5 years. At the last follow-up, the mean range of flexion/extension range of motion (% of normal side) improved from 52.8 ± 5.4% to 65.7 ± 11.1%, P = 0.002, the mean grip strength (% of normal side) improved from 54.6 ± 11.8% to 88.3 ± 12.4%, P = 0.001, the mean Mayo Wrist Score improved from 41.5 ± 8.2 to 81 ± 9.2, P = 0.002, and the mean VAS score reduced from 6.1 ± 1.6 to 0.6 ± 0.4, P = 0.004. The mean follow-up MCHR improved from 1.46 ± 0.11 to 1.59 ± 0.34, P = 0.112. The mean radioscaphoid angle improved from 63 ± 10º to 49 ± 6º, P = 0.011. The mean scapholunate angle increased from 32 ± 6º to 47 ± 8º, P = 0.004. The mean modified carpal-ulnar distance ratio was preserved and none of the patients developed ulnar translocation of the carpal bones. Radiological union was achieved in all patients. CONCLUSIONS: Scapho-luno-capitate fusion with partial lunate excision and preservation of the proximal lunate surface is a valuable option for treating stage IIIA Kienböck's disease, with satisfactory outcomes. Level of evidence Level IV. Trial registration Not applicable.

Volar and Dorsal Blood Supply to the Lunate: A Cadaveric Study.

Although various studies have proposed vascular and mechanical factors, the etiology of Kienböck disease is unknown. Kienböck theorized that lunatomalacia resulted from traumatic disruption of blood supply and bony nutrition to the lunate. Extraosseous supply to the lunate, as far as volar or dorsal vessels are concerned, is still controversial. This study evaluated the extraosseous nutrient foramina from the dorsal and volar aspects of lunate specimens. A total of 913 specimens from the Hamann-Todd Osteological Collection in Cleveland, Ohio, were examined. The nutrient artery foramina on left and right lunate specimens were examined from dorsal and volar aspects. The number of nutrient artery foramen was tabulated. Age, sex, and race data were collected. Specimens were divided into groups according to the number of nutrient artery foramina, and the dorsal and volar foramina were compared. The average number of foramina on the dorsal aspect of the lunate (1.71) was greater than the volar aspect (1.64), except in specimens younger than 35 years. A greater number of specimens had 3 or more foramina on the dorsal side compared with the volar aspect. Based on this study, there was significant contribution of dorsal arterial vessels to the blood supply of lunate specimens older than 35 years, which contrasts with findings in earlier studies. The disruption of dorsal intercarpal and radiocarpal ligaments leading to the disruption of the dorsal arterial arches may contribute to vascular insufficiency of the lunate and should be evaluated further in the etiopathogenesis of Kienböck disease. [Orthopedics. 2021;44(2):e243-e247.].

Osteonecrosis of the Lunate: Kienböck Disease.

Kienböck disease, osteonecrosis of the lunate, is a well-known but poorly understood complication seen by hand surgeons. This review presents the background and important patient-specific parameters of the disease and reviews the numerous treatment options that exist for the disease.

Superselective angiography of the wrist in patients with Kienböck's disease.

BACKGROUND: Microvascular problems like increased intraosseous pressure or venous congestion may influence the development of Kienböck's disease. We examined if wrist position modifies the blood flow in the nutrient vessels. METHODS: Retrospective analysis of 17 patients with Kienböck's disease who had a superselective microangiography of the radial, ulnar and interosseous artery in different wrist positions under general anaesthesia. We analysed the data with Fisher's exact and Wilcoxon-test. RESULTS: We found vessels that entered the bone, that ended at the bone edge, and that supplied a vascular plexus. The origins were the anterior interosseous artery in 10 of 17 cases, the radial artery in seven cases, and the ulnar artery in five cases. Movement of the wrist could reduce or stop the blood flow. Type of lunate configuration showed no significant influence on the blood supply in neutral position. CONCLUSION: The radial, ulnar, and anterior interosseous artery contribute to the vascular supply of the lunate bone in different combinations. Wrist movement can reduce blood flow to the lunate bone.

A Three-Dimensional Micro-Computed Tomographic Study of the Intraosseous Lunate Vasculature: Implications for Surgical Intervention and the Development of Avascular Necrosis.

BACKGROUND: The purpose of this study was to use micro-computed tomography to demonstrate the intraosseous vascularity of the lunate within a three-dimensional orientation to identify areas of greatest perfusion and define vascular "safe zones" for surgical intervention. METHODS: Fourteen upper extremities were injected with a lead-based contrast agent. The lunates were harvested and scanned using a micro-computed tomography scanner. The intraosseous vascularity was incorporated into a three-dimensional image. Vessel number, diameter, distribution, and pattern were evaluated and analyzed. Vascularity of all specimens was projected onto one representative lunate to identity areas of higher and lower vascularity. RESULTS: Twelve specimens had nutrient vessels entering the bone from volar and dorsal; two specimens had no dorsal vessels. The intraosseous vascularity could be classified according to the Y, I, and X patterns described by Gelberman et al. Average number and diameter of vessels were 2.3 and 118.1 µm, respectively, for volar; and 1.4 and 135.8 µm, respectively, for dorsal. The long axis of the lunate showed the highest vascularity on both axial and lateral views. Lower vascularity was observed in the dorsoradial and volar-ulnar quadrants on the axial view, and in the proximal part on the lateral view. Lunate shape was not associated with an increase or decrease in nutrient vessels or vascular pattern. CONCLUSIONS: Vascular safe zones were identified, allowing for potentially safer surgical interventions to the lunate. Volar approaches to the lunate may result in localized ischemia in a subset of patients with absent dorsal nutrient vessels. This study may help to better define patients at risk for Kienböck disease.

Keyhole Revascularization for Treatment of Coronal Plane Fracture of the Lunate in Kienböck Disease.

Coronal plane fracture of lunate in Kienböck disease is a challenging problem with no proven treatment. We present a technique for the treatment. A vascularized bone graft from the distal radius employing the fourth and fifth extracompartmental artery pedicles is used as a mechanical support in order to enable fracture union. The technical pearls and pitfalls are described and a clinical case is presented.

Treatment of Kienböck's disease using a fourth extensor compartmental artery as a vascularized pedicle bone graft.

BACKGROUND: Vascularized bone grafts for the treatment of Kienböck's disease may facilitate revascularization and remodeling of the avascular lunate. The aim of this study was to evaluate the radiological and clinical results obtained when a fourth extensor compartmental artery (ECA) bone graft was used to treat Kienböck's disease. METHODS: Between May 2009 and June 2012, 13 patients (6 men, 7 women) with Kienböck's disease were treated with placement of fourth ECA vascularized bone grafts. The mean patient age was 39.2 (20-58) years, and the mean follow-up period was 32.5 (12-72) months. At the time of surgery, One patient had Lichtman's stage II Kienböck's disease, 11 stage IIIA disease, and one stage IIIB disease. We measured the pre- and post-operative ranges of motion, pain, grip strength, and radiological parameters, including the carpal height ratio and the radioscaphoid angle. RESULTS: At the last follow-up, pain was significantly reduced, and grip strength had improved from 60.5% to 87.8% relative to that of the contralateral side. The mean range of motion for flexion had improved from 39° to 53° while that of wrist joint extension improved from 41° to 56°. There were little or no changes in either the carpal height ratio or the radioscaphoid angle (both p values > 0.05). CONCLUSIONS: Placing of a fourth ECA vascularized bone graft is a reliable alternative to other revascularization procedures for treatment of Kienböck's disease. Such grafting is effective, minimally invasive, and associated with a low risk of pedicle kinking. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic/IV.

Kienböck Disease: Recent Advances in the Basic Science, Assessment and Treatment.

Kienböck disease is a disorder of impaired lunate vascularity which ultimately has the potential to lead to marked degeneration of the wrist and impaired wrist function. The aetiology of the avascular necrosis is uncertain, but theories relate to ulnar variance, variability in lunate vascularity and intraosseous pressures. Clinical symptoms can be subtle and variable, requiring a high index of suspicion for the diagnosis. The Lichtmann classification has historically been used to guide management. We present a review of Kienböck disease, with a focus on the recent advances in assessment and treatment. Based on our understanding thus far of the pathoanatomy of Kienböck's disease, we are proposing a pathological staging system founded on the vascularity, osseous and chondral health of the lunate. We also propose an articular-based approach to treatment, with an arthroscopic grading system to guide management.

Partial capitate shortening for Kienböck's disease.

The purpose of this study was to report our experience of partial capitate shortening in seven patients with a median 38 months follow-up. Staging was made by the Lichtman classification system and stage II and III-A patients were included in the study. The mean age was 34 years (range 22-52). Patients were assessed for pain, range of motion, grip and pinch strength, and satisfaction was recorded using a scale between 0 and 4. All these parameters showed improvement after surgery. The Lichtman stage, lunate height index and carpal height index were determined radiographically. Magnetic resonance images of the wrist were studied for lunate revascularization at the final follow-up and occurred in all patients. According to our study, partial capitate shortening seems an effective treatment for Lichtman stage II and III-A patients.Level IV case series study.

Kienböck disease.

Kienböck disease, or osteonecrosis of the lunate, most often affects patients between the ages of 20 and 40 years. There are 4 major stages of the disease, and treatment is based on the stage of disease. Advancements are still being made with regards to the cause, pathophysiology, and preferred method of treatment of each stage. Although the goals of pain relief, motion preservation, strength maintenance, and function outcomes are paramount to success, no 1 procedure consistently and reliably achieves these outcomes. Further advancements in treatment and results of long-term outcome studies should resolve some of these topics.

Vascularized bone transfer for the treatment of advanced-stage juvenile lunatomalacia: a report of two cases.

We present the first two cases of juvenile patients, with advanced-stage lunatomalacia (Lichtman stage IIIB) in the literature, who were successfully treated with vascularized bone transfers. A corticoperiosteal metacarpal II bone graft was used in both patients, accompanied by an external monorail fixateur that was mounted for 6 weeks to achieve temporary wrist distraction. At 1-year follow-up, the patients had no residual pain, full wrist range of motion, and proper radiologic remodeling of the collapsed lunate. Surgically diminished compression forces at wrist level, temporary gain of joint width, as well as high juvenile potential for remodeling might have enhanced lunate revascularization.

A hand therapy protocol for the treatment of lunate overload or early Kienbock's disease.

We describe a hand therapy protocol aimed at unloading the wrist and increasing blood supply to the wrist, specifically to the lunate. The protocol was used in a series of patients with clinical radial wrist pain, dysfunction and changes on wrist imaging studies. The patients were not candidates for surgical treatment. Application of the therapy protocol improved objective and subjective parameters such as pain and motion, and may provide a viable treatment option for patients with lunate overload or early Kienbock's disease that are not candidates for surgery.

Long-term clinical and radiological outcomes of radial shortening osteotomy and vascularized bone graft in Kienböck disease.

PURPOSE: To evaluate the long-term (> 5 y) outcomes of radial shortening osteotomy and vascularized bone graft in Kienböck disease patients. METHODS: In a retrospective study of 16 patients with early stage Kienböck disease, 9 patients with average follow-up of 6.4 years had radial shortening osteotomy (group 1), and 7 with average follow-up of 6.5 years had pedicled vascularized bone graft based on the distal radius 4 + 5 extensor compartmental artery (group 2). The 2 groups were similar in age, sex, operated side, initial Lichtman stage, and follow-up duration. There were significant differences in ulnar variance between the 2 groups. At the last follow-up, the patients were evaluated for pain, wrist motion, grip strength, functional status, and radiographic assessment. The overall results were evaluated by Cooney wrist function score and Nakamura scoring system for Kienböck disease. RESULTS: The 2 groups had no significant difference in pain, motion, grip strength, and radiologic assessment; however, grip strength percentage was better in group 2. There was no significant difference between the radiographic changes of the 2 groups. In group I, 7 out of 9 patients had satisfactory Nakamura scores, and 5 out of 9 patients had satisfactory Cooney scores. All of the patients in group 2 had satisfactory Cooney and Nakamura scores. The difference in the mean Cooney wrist function score in the 2 groups was significant. The difference of Nakamura scores in the 2 groups was not significant. CONCLUSIONS: Both groups had reasonable long-term outcomes. We were unable to recognize a substantial clinical or radiological difference between the 2 surgical treatments in long-term outcome. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.

Kienböck disease.

Kienböck disease, or osteonecrosis of the lunate, is a progressive disease process that can lead to wrist pain and dysfunction. Although it was described over 100 years ago, and advances have been made in understanding this disease, the precise etiology remains uncertain. Anatomic, mechanical, vascular, and traumatic factors have been suggested to contribute to the disease. The natural history is unknown, and radiographic and clinical findings do not always correlate. Progress has been made in recognizing the progression of the avascular process and its deleterious effects on wrist mechanics. Initial treatment is nonsurgical, and it remains unclear whether surgical intervention results in improved outcomes over nonoperative treatment. Traditional surgical procedures such as radial shortening osteotomy and proximal row carpectomy have been shown to be reliable treatment options for relieving pain and improving function. Newer procedures such as pedicled bone grafts from the distal radius may improve direct revascularization of the lunate in earlier stages of the disease, potentially arresting the progression of collapse. Additional data are necessary to determine with certainty whether this type of procedure represents an improvement over the traditional treatment alternatives. Kienböck disease remains a challenging problem for hand surgeons.

Etiology of Kienböck disease.

The etiology of Kienböck disease is still unknown and, consequently, the ideal treatment is in doubt. Many different hypotheses have been suggested. There are reasons to believe that there are mechanical, vascular, and metabolic factors predisposing to the disease, and probably some factors triggering the development of the process. Among mechanical factors, the short ulna has been thought to be the most relevant. However, presently there are insufficient data to support a significant association between negative ulnar variance and Kienböck disease. With regard to vascular factors, anatomical studies have shown consistent dorsal and palmar arteries entering the bone, and thus, the most likely site for vascular impairment may be at the subchondral level. Many triggering factors have been proposed during the past years, but until this is truly clarified, finding the real cause of Kienböck disease will continue to be a real challenge.

Revascularization procedures for Kienböck disease.

The goals of treatment in Kienböck disease include preservation of wrist function, maintaining normal wrist kinematics, and revascularization of the necrotic lunate when and if possible. A variety of pedicled vascularized bone graft options exist and include but are not limited to pedicled grafts from the volar radius, dorsal radius, metacarpal heads or bases, and pisiform. Of the various treatment options, pedicled vascularized bone grafts from the dorsal distal radius based on the fourth and fifth extensor compartment arteries has been successful in the revascularization of the necrotic lunate at our institution. Vascularized bone grafting is an attractive alternative to conventional bone grafting by improving the local biological environment and thereby promoting revascularization. Recent advances in the anatomy and physiology of vascularized pedicled bone grafts have increased our ability to apply them to the treatment of Kienböck disease. The purpose of this article is to describe the various types of pedicled vascularized bone graft available, to detail the vascular anatomy of the dorsal distal radius, and to describe the surgical technique of our preferred vascularized bone graft (the fourth+fifth extensor compartment artery graft). In addition, the indications, contraindications, and outcomes are described.

Study of vascular supply of lunate and consideration applied to Kienböck disease.

The purpose of this study was to assess vascularity of the lunate by number of foramina and radiography of vessels of the wrist. The genesis of lunatomalacia requires some vascular risk and mechanical predisposition. The findings were correlated with the cause of Kienböck's disease. The vascular foramina were more than two in 91.33% of the lunate. The lunate had consistent dorsal and palmar branches from radial artery. The additional branches from anterior interosseous artery in 72.22% and a branch of palmar inter carpal arch in 69.44% cases contributed in arterial anastomosis on palmar aspect of lunate. The dorsal blood supply was found by anterior interosseous artery in 85.71% of specimens and dorsal branch from dorsal intercarpal arch in 50% of specimens. The blood supply of lunate comes along with various ligaments which may be disrupted due to trauma or strain leading to avascular necrosis. The present observations are suggestive of rich blood supply of lunate in comparison of other investigations. Therefore Kienböck's disease is less common in northern India.