Non-vascularized partial joint transfer for Finger Proximal Interphalangeal joint reconstruction: a series of 9 patients.

INTRODUCTION: Finger proximal interphalangeal joint (PIP) reconstruction after the destruction of parts of the joint remains challenging. Surgical techniques include implant arthroplasty, arthrodesis, free vascularized joint transfer, and non-vascularized bone and joint transfer. This study analyzes our experience after non-vascularized transfer in terms of range of motion, postoperative rehabilitation, and patient satisfaction. MATERIALS AND METHODS: Between 2009 and 2014, ten patients underwent non-vascularized partial joint transfer for PIP joint reconstruction. One of them was lost to follow-up. Included patients had osteochondral partial joint transplants of 25-50% of the toes (n = 4) and the hand (n = 5). Range of motion (ROM), grip-, and pinch-strength were measured at the last follow-up control and compared to the healthy side. Patients were asked to score the pain at rest/ on load on a visual scale (VAS: 0 = no pain; 10 = excruciating pain). Satisfaction self-assessment was evaluated by asking the patients to grade their postoperative result as excellent, very good, good or poor. RESULTS: Mean follow-up period was 4.0 years (range 1.2-7.9 years). Mean PIP joint flexion was 93 ± 26° at the last follow-up control. Mean grip- and pinch-strength of the operated side at the last control were, respectively, 43 ± 18 kg and 8 ± 5 kg, close to the healthy side values (45 ± 15 kg and 9 ± 4 kg). Mean pain at rest/on load measured on a visual scale was, respectively, 0.3 ± 1 and 1.8 ± 2. Eight patients (89%) rated their operation as excellent, and one as poor. CONCLUSION: In this study, non-vascularized partial joint transfer provides a mobile and stable PIP joint 4 years after reconstruction. The surgical technique presented herein is complex depending on additional injuries but results in great patient satisfaction.

Heterotopic Vascularized Joint Transfer in Mutilating Hand Injuries.

BACKGROUND: In cases of mutilating hand injuries, the primary goal is recovery of prehensile function. This is particularly true in the case of joints, which are extremely difficult to replace or reconstruct adequately when damaged. Heterotopic vascularized joint transfer is indicated when salvageable joints are available for transfer to a more functionally optimal position on the hand. MATERIALS AND METHODS: Seven cases of mutilating hand injuries treated with heterotopic vascularized joint transfers from 2003 to 2012 were retrospectively identified. All patients sustained severe metacarpophalangeal joint (MPJ) or proximal interphalangeal joint (PIPJ) damage that threatened recovery of optimal hand function. All patients were men, with an average age of 34.7 years. Operative, perioperative, and postoperative details including final active range of motion were collected and analyzed. RESULTS: Seven joints were taken from nonsalvageable amputated digits: 4 from the amputated parts, and 3 from the proximal stumps. Five joints were transferred as free flaps requiring microvascular anastomosis, and 2 were transferred on neurovascular pedicles. One joint was lost due to vasospasm. Average active range of motion was 68.3° for homojoint transfers (MPJ to MPJ, PIPJ to PIPJ), and 35° for heterojoint transfers. All but 1 patient were able to achieve tripod pinch; the remaining patient achieved only side-to-side pinch. CONCLUSIONS: Heterotopic vascularized joint transfer is a useful technique to consider in cases of mutilating hand injuries. Improved recovery of prehensile function can be achieved with thoughtful design and execution, followed by proper patient education and rehabilitation.

Possibility of the hamatum carpometacarpal joint as a new joint donor site for interphalangeal joint restoration.

OBJECTIVE: This research investigates the anatomic basis for the repair and reconstruction of hand joints using transposition of the carpometacarpal (CMC) joint of the hamatum. METHODS: The morphology and structure of the CMC joints of the hamatum and the base joints of the middle phalanx were observed on 22 freshly frozen wrist specimens at Shanghai 6th People's Hospital Research Institute of Microsurgery. The volar dorsal dia, radioulnar dia, depth of concave, and area of the joints were measured. Data were obtained through statistical analysis, and the resemblance of joints was compared in terms of morphology, structure, area, length, and diameter. RESULTS: The radioulnar dia of the CMC joints of the hamatum (13.54 ± 1.15 mm) did not exhibit any evident differences in the middle phalanx of the forefinger, middle finger, and ring finger, and in the distal phalanx of the thumb. The volar dorsal dia of the CMC joints of the hamatum (10.71 ± 0.93 mm) exhibited an evident difference in the middle phalanx of the ring finger. In all fingers, the depth of the ulnar and radial concave of the CMC joints of the hamatum (1.30 ± 0.08 and 0.95 ± 0.05 mm, respectively) and the area of the CMC joints of the hamatum (139.89 ± 5.44 mm(2)) showed an evident difference. CONCLUSION: The CMC joint of the hamatum could be considered a new and viable joint donor site that could be used to repair and reconstruct the base joints of the middle phalanx.

Toward regeneration of articular cartilage.

Articular cartilage is classified as permanent hyaline cartilage and has significant differences in structure, extracelluar matrix components, gene expression profile, and mechanical property from transient hyaline cartilage found in the epiphyseal growth plate. In the process of synovial joint development, articular cartilage originates from the interzone, developing at the edge of the cartilaginous anlagen, and establishes zonal structure over time and supports smooth movement of the synovial joint through life. The cascade actions of key regulators, such as Wnts, GDF5, Erg, and PTHLH, coordinate sequential steps of articular cartilage formation. Articular chondrocytes are restrictedly controlled not to differentiate into a hypertrophic stage by autocrine and paracrine factors and extracellular matrix microenvironment, but retain potential to undergo hypertrophy. The basal calcified zone of articular cartilage is connected with subchondral bone, but not invaded by blood vessels nor replaced by bone, which is highly contrasted with the growth plate. Articular cartilage has limited regenerative capacity, but likely possesses and potentially uses intrinsic stem cell source in the superficial layer, Ranvier's groove, the intra-articular tissues such as synovium and fat pad, and marrow below the subchondral bone. Considering the biological views on articular cartilage, several important points are raised for regeneration of articular cartilage. We should evaluate the nature of regenerated cartilage as permanent hyaline cartilage and not just hyaline cartilage. We should study how a hypertrophic phenotype of transplanted cells can be lastingly suppressed in regenerating tissue. Furthermore, we should develop the methods and reagents to activate recruitment of intrinsic stem/progenitor cells into the damaged site.

Autogenic heterotopic vascularized proximal interphalangeal joint transplantation in children.

The proximal interphalangeal joint (PIP) joint is the most crucial joint for the functionality of a finger. For a child with complex injury of the hand every effort should be exercised to maximize function restoration. If the PIP joint is irreparably damaged, its reconstruction is indicated. The technique of autogenic heterotopic vascularized toe joint transplantation provides unique advantage of a composite transfer of skin, tendons, bone and joint alone with growth plate and its efficacy has been affirmed in children. It has been suggested that such transfers require intact flexor tendon to achieve satisfactory results, our experience however indicates quite the contrary. As evidenced by this report of a 7-year-old boy with abrasion and avulsion injury to his dominant right hand resulting in a complex defect with skin lose, extensor, flexor avulsion along with cominution of the PIP joint of his long finger. A surgical formulation of staged reconstruction scheme including an autogenic heterotopic vascularized toe joint transplantation led to complete functional restoration to his right hand.

A modified vascularized whole knee joint allotransplantation model in the rat.

Previous papers have shown surgical neoangiogenesis to allow long-term bone allotransplant survival without immunosuppression. Whole joint composite tissue allotransplants (CTA) might be treated similarly. A novel rat knee CTA model is described for further study of the roles of neoangiogensis in joint allotransplant survival and adjustment of immunosuppression. Microvascular knee CTA was performed in nine rats across a major histocompatibility barrier with both pedicle repair and implantation of host-derived arteriovenous ("a/v") bundles. In the control group (N = 3), the pedicle was ligated. Immunosuppression was given daily. Joint mobility, weight-bearing, pedicle patency, bone blood flow, and sprouting from a/v bundles were assessed at 3 weeks. All but the nonrevascularized control knees had full passive motion and full weight bearing. One nutrient pedicle thrombosed prematurely. Blood flow was measurable in transplants with patent nutrient pedicles. Implanted a/v bundles produced new vascular networks on angiography. This new rat microsurgical model permits further study of joint allotransplantation. Patency of both pedicles and implanted a/v bundles was maintained, laying a foundation for future studies.

Vascularized second metatarsophalangeal joint transfer for radial deficiency - an update.

Vascularized second metatarsophalangeal joint transfer offers a possibility to reconstruct the radial support which is lacking in radial dysplasia. Our experience from 1987 to 2017 with 34 congenital radial club hand reconstructions have allowed a possibility for long-term evaluation of the method. Compared with conventional methods, second metatarsophalangeal joint transfer results in better wrist mobility and does not restrict typical ulnar growth. The balance of the wrist remains good until age 11. Thereafter, the growth of the vascularized bone graft transfer matches only partially the distal ulnar growth in adolescence, resulting in mild recurrence of radial deviation. A new option to create a two-bone forearm in selected Bayne-Klug Type III radial dysplasia cases will allow a relatively good pro-supination ability. Potentially, a proximal fibular epiphyseal transfer could be a future solution. Currently, a safe harvest of the proximal fibula at childhood remains controversial.

Functional and morphological outcome of knee joint transplantation in dogs depends on control of rejection.

BACKGROUND: The reconstruction of massive osteochondral defects extending to weight-bearing joints remains a surgical challenge. Total knee joint transplantation has been performed experimentally, but these studies lacked prospective evaluation of functional outcome, graft vascularization, and graft viability. METHODS: Replantation and transplantation of vascularized knee joints was performed in dogs (n=4 per group), comparing functional and morphological results during a 6-month follow-up. RESULTS: All replant recipients and three transplant recipients survived the 6-month follow-up period. At this time, duplex sonography and angiography revealed patent anastomoses in all animals. Increases in volumetric flow rates and vascular collateralization were observed in allografts, as compared with replanted joints (100+/-16 ml/min vs. 31+/-15 ml/min at 6 months after transplantation). Bone fusion at the graft-host interface was verified by fluorography in all animals at 3 months after transplantation. Six months after transplantation, microradiographies and computerized tomographies revealed spongialization of the cortical bone and filling of the medullary space by trabecular bone in transplanted joints. Such alterations were not detectable in replanted joints. Chondrocyte viability exceeded 80% in all but one transplanted joint. Lymphocyte infiltration of synovia and arterial walls was detected in all transplanted joints, suggesting the presence of chronic rejection. Weight-bearing capacity recovered in all replanted animals (weight-bearing index before transplantation: 0.499+/-0.080; 6 months after transplantation: 0.38+/-0.16) but only in two of four transplanted animals (weight-bearing index 6 months after transplantation: 0.37, 0.28, and 0.00). CONCLUSIONS: These data demonstrate the potential of joint grafting and the critical dependence of allotransplantation on the control of rejection.

Joint changes in transplanted caudal vertebrae.

Both straight and bent segments of tails from 4-d-old and weaning Sprague-Dawley rats were used to study the changes which occur in symphyseal joints on transplantation to non-functional sites. In the joints from the younger donors ankylosis occurred almost invariably in the proximal end of the tail, while distally it was rarely seen unless the tail was curved, when ankylosis was visible on the inner side of the bend. The joints from the older donors showed a more varied response on transplantation. Some appeared unaltered, in others where growth continued, calcific changes were seen. In bent segments, unlike in younger ones, ankylosis occurred preferentially on the outer side of the bend. Histological examination revealed that ankylosis of the joint occurred through a process of chondroid metaplasia of the intervertebral connective tissue with subsequent replacement by bone. The metaplastic joint changes were primarily the results of pressure producing compression of the annulus fibrosus in tissues with a reduced vitality due to transplantation and lack of function.

Bone and joint surgery--looking ahead.

Looking ahead, one envisions an era of remarkable progress in the study of the healing of bone and cartilage. The physical, biochemical, and biomechanical factors governing bone and cartilage healing will be defined and manipulated to accelerate the healing process. Joint stiffness, the undesirable sequela of many simple fractures of the hand as a result of prolonged immobilization, will be obviated. For cases of limited joint damage, techniques for joint reconstruction will be refined. For non-salvageable bone and joint destruction, microvascular allogenic transplantation of skeletal units will become a reality. Silastic implants in the wrist will become historical oddities.

Massive allografts in surgery of bone tumors.

Large osseous and osteoarticular allografts have provided the orthopedic oncologist with a useful biological reconstructive alternative following wide en-bloc resection of bone tumors. Although the surgical procedures are complex, meticulous surgical techniques in terms of graft selection, allograft fixation, reconstruction of joint ligaments and tendons, and adequate skin coverage would produce satisfactory results in about three quarters of the patients. The potential causes of failure include allograft fracture, infection, nonunion and joint instability.

Experimental transplantation of small joints by microvascular anastomoses.

Metacarpophalangeal joints in dogs were transplanted with microvascular anastomoses. Some were transplanted as half-joints, others as whole joints, and these dogs were followed for up to 5 1/2 months. When a half-joint was transplanted within the foot, the joint movement became restricted but the vascularized half-joints were well preserved with only slight damage and well-preserved epiphyseal plates--compared to severe damage of the articular cartilage and destruction of the epiphyseal plates in the non-vascularized joint transplants. Vascularized whole joint transplants within the foot were indistinguishable macroscopically and microscopically from normal joints, and they had only a slight restriction of joint movement. They took up tetracycline from the circulation, demonstrating their viability.

Free vascularized toe joint transfer to the hand. A technique for simultaneous reconstruction of the soft tissue.

Twelve patients underwent reconstruction of injured finger joints using our technique of a vascularized transfer of the second toe proximal interphalangeal joint. The age of the patients at operation ranged from 7 to 47 years and the postoperative follow-up was 9 to 48 months. All the joint transfers survived and united with resolution of the preoperative joint pain, deformity and instability. The average range of motion of the reconstructed joints was 59 degrees in the proximal interphalangeal and 54 degrees in the metacarpophalangeal joints. No patient complained of pain or functional deficits in the donor foot.

Treatment of traumatic arthritis in children.

Although alternatives do exist for the treatment of traumatic arthritis in children, all efforts should be directed to treat the initial condition to avoid its progression to arthritis. Once arthritis is established, then follow the axiom, "treat patients, not x-rays." If despite all attempts at conservative treatment, a surgical option is necessary, then attention must be given to potential future growth, joint stability, and alignment, pain relief, and anticipated postoperative range of motion. All cases must be individualized because, unfortunately, none of the alternatives available is capable of guaranteeing a "normal" end result.

Survival of 25 osteoarticular allografts followed more than 10 years.

An evaluation of the long-term survival rate of 25 osteoarticular allografts was made. Clinical analysis was based on the Mankin scale and the Musculoskeletal Tumor Society (MSTS) Grading system. After a mean follow-up time of 15 years 76% of the osteoarticular allografts had good or excellent rating. The MSTS scale revealed a mean score of 89% for those 20 grafts still functioning according to their primary purpose. Allograft related complications occurred in 32% of the cases being most common among malignant cases. Due to the rather good long-term results, osteoarticular allografts can still be recommended for hemicondylar allograft reconstruction in benign lesions.

Improving the extensor lag and range of motion following free vascularized joint transfer to the proximal interphalangeal joint: Part 1. An observational and cadaveric study.

BACKGROUND: Extension lag is a common occurrence following free vascularized joint transfer reconstruction of the proximal interphalangeal joint, thus limiting the range of motion that is achievable. In this Part 1 study, the anatomical and biomechanical arrangements of the toe proximal interphalangeal joint extensor mechanism were investigated. METHODS: Twelve second toes from 12 fresh cadavers were dissected for examination of the extensor mechanism. Similar observations were performed in nine clinical cases. A total of 21 toes were therefore examined with dynamic and static testing. RESULTS: In 17 toes, the central tendon attenuated before inserting onto the middle phalangeal base (type I). In four toes, a thicker tendinous insertion analogous to a central slip was identified (type II). In type I toes, traction of the extensor digitorum brevis and digitorum longus did not correct the extensor lag. The extension lag decreased when the metatarsophalangeal joint was flexed passively or when both extrinsic and intrinsic tendons were pulled simultaneously. In type II toes, a full extension of the proximal interphalangeal joint was achieved when the extensor tendons were pulled with or without pulling the intrinsic tendons. In both types of toes, there was an increase in the extension lag caused by dorsal bowstringing when separated from the extensor sling. CONCLUSIONS: The lesser toe proximal interphalangeal joint adopts a naturally flexed posture for evolutionary reasons, with corresponding adaptations in extensor mechanism arrangements. The most significant limiting factor to full extension could be the presence of an attenuated central slip in the majority of toes.

Improving the extensor lag and range of motion following free vascularized joint transfer to the proximal interphalangeal joint: Part 2. A clinical series.

BACKGROUND: Free vascularized joint transfer for reconstructing the posttraumatic proximal interphalangeal joint has enjoyed limited popularity because of the low range of motion typically achieved after transfer. One of the commonest complaints is the significant extensor lag. Part 2 of this two-part study is focused on the clinical outcomes following a more anatomical approach to extensor tendon reconstruction. METHODS: Nine patients (eight male and one female), with a mean age of 31.7 years, underwent free vascularized joint transfer for posttraumatic proximal interphalangeal joint injuries using the second toe proximal interphalangeal joint. In Part 1, two arrangements of the central slip mechanism were found: type I with an attenuated and type II with a distinct central slip. An algorithm was constructed using this information: in a type I toe with sufficient recipient lateral bands, a centralization procedure was carried out; and when the lateral bands were insufficient, a modified Stack procedure was carried out. In type II toe joints, a tight repair of the corresponding extensor tendons was performed. RESULTS: Four patients underwent centralization procedures, two underwent a modified Stack procedure, and three underwent tight extensor repair. At 23.4 months, the average extensor lag was 18.3 degrees. A total range of motion of 53.9 degrees (mean flexion, 72.2 degrees) was achieved that approximated 81.1 percent of the pretransfer passive range of motion at the toe proximal interphalangeal joint. CONCLUSION: This preliminary result demonstrates that much improved range of motion can be achieved by reducing the extensor lag using an anatomical reconstruction that takes into account the recipient finger and toe joint anatomy. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

[Experimental study on protective effect of early motion on articular cartilage after joint allograft].

OBJECTIVE: To investigate the protective effect of early motion on articular cartilage after joint allograft by performing a controlled trial between different post-operation strategies after joint allograft in an animal model. METHODS: Twenty hemi-knee joints were harvested from 10 6-month-old New Zealand white rabbits (male or female, weighing 2.5-3.0 kg); 10 hemi-knee joints by deep frozen treatment (donors) were transplanted to unilateral knee joints (recipients) of 10 6-month-old Chinchilla rabbits (male or female, weighing 2.5-3.0 kg), which were divided into early motion group (n = 5) and sustained fixation group (n = 5); and 10 hemi-knee joints were used as blank control (n = 5) and frozen control (n = 5). The articular cartilage of allogenic joints was detected by X-ray film, gross, and histology at 6 weeks after operation. RESULTS: Gross observation: no obvious limitation of joint movements was observed in early motion group, but obvious limitation in sustained fixation group. X-ray films: the bone ends between donor and recipient healed well with good para position and alignment on the operation day and 2 weeks after operation; at 6 weeks, angulation deformity was observed in early motion group of 3 rabbits, and para position and alignment were satisfactory in sustained fixation group. Histological observation: HE staining showed that the chondrocytes had normal quantity and morphology with few nuclear fragmentation and karyolysis in early motion group, but the quantity of chondrocytes sharply decreased with dissolved nuclei and numerous fibrous tissues in the cartilage matrix in sustained fixation group. The cell survival rate of the early motion group (49.66% +/- 2.15%) was significantly higher than that of the sustained fixation group (20.68% +/- 1.24%) (P < 0.05). Scanning electron microscopy observation: nuclear membrane was intact with chromatin condensation and edema of mitochondria and rough surfaced endoplasmic reticulum in early motion group, and that the membrane of chondrocyte vanished with blurring border between chondrocyte and matrix, rupture of nuclear membrane and the disappearance of chromatin and organelles could be found in sustained fixation group. CONCLUSION: Early motion has protective effect on articular cartilage after joint allograft, but cannot completely prevent degeneration of the allogenic articular cartilage.

Changing paradigms in the treatment of radial club hand: microvascular joint transfer for correction of radial deviation and preservation of long-term growth.

Radial longitudinal deficiency, also known as radial club hand, is a congenital deformity of the upper extremity which can present with a spectrum of upper limb deficiencies. The typical hand and forearm deformity in such cases consists of significant forearm shortening, radial deviation of the wrist and hypoplasia or absence of a thumb. Treatment goals focus on the creation of stable centralized and functionally hand, maintenance of a mobile and stable wrist and preservation of longitudinal forearm growth. Historically centralization procedures have been the most common treatment method for this condition; unfortunately centralization procedures are associated with a high recurrence rate and have the potential for injury to the distal ulnar physis resulting in a further decrease in forearm growth. Here we advocate for the use of a vascularized second metatarsophalangeal joint transfer for stabilization of the carpus and prevention of recurrent radial deformity and subluxation of the wrist. This technique was originally described by the senior author in 1992 and he has subsequently been performed in 24 cases with an average of 11-year follow-up. In this paper we present an overview of the technique and review the expected outcomes for this method of treatment of radial longitudinal deficiency.

Skeleton pattern and joint formation in chorioallantoic grafts containing the distal parts of the chick wing bud.

Skeleton pattern formation was examined in chick wing bud grafts using the chorioallantoic grafting method. The distal parts of the wing bud were excised from the donor wing and transplanted onto the chorioallantoic membrane (the experimental groups). Transplants with intact limb bud material served as the control group. The skeleton pattern formation in the grafts depended on the amount of transplanted material and donor's limb bud stage. The younger the donor's stage and the bigger the piece of the transplanted material the more proximal parts grafts had, more retarded growth and abnormal skeleton in the zeugopod and autopod was. The percentage of the signs of insufficient blood supply in the experimental groups was less than that in the control group. As the amount of the transplanted limb bud material decreased and donor's limb bud aged, post-axial polydactyly changed to the pre-axial one.