One-stage reconstruction of skin defect and patellar tendon rupture after total knee arthroplasty. A new technique

A Systematic Review of Clinical Outcomes of Pedicled Flap Repairs of the Knee Extensor Mechanism

BACKGROUND

 Rupture of the extensor mechanism of the knee has severe functional morbidity, and repair can be complicated by infection, allograft degeneration, and recurrent rupture. Techniques of autologous tissue repair utilizing pedicled flaps such as the gastrocnemius offer vascularized methods of reconstruction, with potentially diminished complication rates. The goal of this study was to evaluate the functional outcomes and complications associated with pedicled flap repair of the knee extensor mechanism.

METHODS

 A systematic review was conducted following the Preferred Reporting Items for Systemic Reviews and Meta-Analyses guidelines. Publications that focused on local myocutaneous flaps as a means for reconstruction were included. Causes for knee extensor mechanism deficit, flap characteristics, ambulation rate, changes in range of motion pre- and postoperation, and postoperative complications were analyzed. Technique reports including primary suture repairs, synthetic mesh, and allograft use were excluded.

RESULTS

 An initial 119 studies were identified, with final review of 22 observational studies encompassing 128 cases of pedicled flap reconstructions. The gastrocnemius (88.2%, n = 113), quadriceps (6.3%, n = 8), and a combination of the vastus and gastrocnemius flaps (5.5%, n = 7), were the most frequently utilized flaps. Functional outcomes were favorable with 87.2% of patients achieving ambulation without external support. Variability in range of motion outcomes across different flap may be secondary to the patient characteristics as well as extent of initial injury.

CONCLUSIONS

 Autologous pedicle flap reconstruction of the knee extensor mechanism emerges as a viable option for cases characterized by extensive defects and insufficient soft tissue coverage, which are not amenable to direct suture repairs or allografts. Postoperative assessments revealed that the majority of patients experienced improved ambulation status, with no instances of deterioration noted among the patients.

The myocutaneous gastrocnemius flap for periprosthetic joint infection of the knee

Purpose

Periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) presents significant challenges, especially in elderly and comorbid patients, often necessitating revision surgeries. We report on a series of patients with confirmed PJI of the knee and concomitant soft-tissue/extensor apparatus defects, treated by using pedicled myocutaneous medial or lateral sural artery perforator (MSAP/LSAP) gastrocnemius flaps.

Methods

Our retrospective study at the Center for Musculoskeletal Infections, included patients with knee PJI undergoing pedicled myocutaneous MSAP/LSAP gastrocnemius flap reconstruction for combined soft tissue and extensor apparatus defects. The tendinous back of the gastrocnemius muscle was used and, if required, the Achilles tendon for extensor apparatus reconstruction, with the skin island addressing the cutaneous defect. Perioperative complications and postoperative outcomes after 1 year were evaluated, including functional and clinical assessments with the American Knee Society Score (AKSS).

Results

Eight patients (mean age 73 years; five female) were included, predominantly with Staphylococcus aureus infections. Six patients involved isolated MSAP flaps, two were extended with the Achilles tendon. The median time for wound healing was 9 days. Short-term follow-up showed successful reconstruction in seven patients, with minor wound dehiscence in one patient. One patient required flap revision for a perigenicular haemato-seroma and two patients were diagnosed with new haematogenous PJI infection. Significant improvement in AKSS scores after surgery was observed (functional AKSS: median 33-85; clinical AKSS: median 64-91, p = 0.001).

Conclusion

Pedicled myocutaneous MSAP/LSAP gastrocnemius flaps offer a safe, reliable and versatile option for reconstructing combined soft tissue and extensor apparatus defects in PJI after TKA. This approach yields excellent functional outcomes with minimal peri- and postoperative complications, which is particularly beneficial in elderly and comorbid patients and feasible in settings without microsurgical availability.

Level of evidence

Level IV.

Patellar Tendon Reconstruction After Failed Primary Repair of Bilateral Ruptures: A Case Report

CASE

A 29-year-old man sustained a bilateral acute patellar tendon rupture (PTR) while jumping on a trampoline. He was initially treated with bilateral transosseous patellar tendon repairs. Bilateral rerupture occurred during a fall 10 weeks after. He subsequently underwent staged bilateral patellar tendon reconstructions using an Achilles tendon allograft. At 3-year follow-up, he has maintained full range of motion and leg strength without rerupture or other complications.

CONCLUSION

The use of Achilles tendon allograft in the presence of inadequate and poor-quality tendon tissue for reconstruction of the patellar tendon in the revision setting is a viable and effective treatment option.

A comparison of healing and complication rates between common flaps utilized in total knee arthroplasty: a review of the literature

Background

Flap reconstruction with perforator, fasciocutaneous, muscular, and/or free microvascular flaps is utilized to cover wound defects and improve vascularization and antibiotic/nutrient delivery. Flap use in revision procedures for total knee arthroplasty has been explored previously; however, current data are limited and studies comparing healing and complication rates between different flap types are lacking.

Methods

A literature review was performed using PubMed on 13 January 2022. Studies were included if they reported healing and complication rates for either gastrocnemius, rectus abdominis, latissimus dorsi, fasciocutaneous, chimeric, or gracilis flaps in the setting of revision total knee arthroplasty (TKA).

Results

The final cohort included gastrocnemius (n = 421, healing rate 73.8%, complication rate 59.9%), gracilis (n = 9, healing rate 93%, complication rate 55.6%), latissimus dorsi (n = 41, healing rate 67%, complication rate 46.3%), rectus abdominis (n = 3, healing rate 100%, complication rate 0%), fasciocutaneous (n = 78, healing rate 70%, complication rate 19.2%), and chimeric flaps (n = 4, healing rate 100%, complication rate 25%). There was no significant difference when comparing healing rates across flap types (p = 0.39). There was a significant difference when comparing complication rates across flap types (p < 0.0001), with a significant difference being noted between gastrocnemius and fasciocutaneous complication rates (p < 0.0001). All other comparisons between flap types by complication rate were not significantly different.

Conclusions

Gastrocnemius flaps are the workhorse flap in the setting of revision TKA, as evidenced by this review. Healing rates did not vary significantly across flap types, which suggests that determining the appropriate flap for coverage of soft-tissue defects in revision TKA should be driven by defect size and location as well as physician experience and patient tolerance.

Staged patellar tendon reconstruction using doubled bone-patellar tendon-bone allograft for infected patellar tendon rupture: a rare case report of three years follow-up

BACKGROUND

Patellar tendon rupture is a relatively rare injury that usually requires surgical treatment. The optimal therapeutic strategy is still controversial, especially when either concomitant patellar tendon infection or soft tissue infection surrounds the patellar tendon. Until recently, most reported reconstruction methods are extensive and difficult to apply because of the poor condition of the soft tissue surrounding the patellar tendon.

CASE PRESENTATION

A 19-year-old male patient presented to our clinic three weeks following a motorcycle accident. There was a 5 x 4 cm sized skin defect with soft tissue infection below the inferior pole of patella. We performed a staged patellar tendon reconstruction using a doubled bone-patellar tendon-bone allograft (BPTB) to the infected patellar tendon rupture, following local random fasciocutaneous flap and split-thickness skin graft. Three months following surgery, the patient was able to perform an active knee motion with no extension lag and excellent clinical functional result.

DISCUSSION AND CONCLUSIONS

Our technique introduced in this specific case is a relatively simple method to reconstruct chronic patellar tendon defects with limited incision exposing only the patellar tendon areas. We expect it can be less invasively performed on patients who have a soft tissue problem and cannot have extensive surgery.

Implementation of Endogenous and Exogenous Mesenchymal Progenitor Cells for Skeletal Tissue Regeneration and Repair

Harnessing adult mesenchymal stem/progenitor cells to stimulate skeletal tissue repair is a strategy that is being actively investigated. While scientists continue to develop creative and thoughtful ways to utilize these cells for tissue repair, the vast majority of these methodologies can ultimately be categorized into two main approaches: (1) Facilitating the recruitment of endogenous host cells to the injury site; and (2) physically administering into the injury site cells themselves, exogenously, either by autologous or allogeneic implantation. The aim of this paper is to comprehensively review recent key literature on the use of these two approaches in stimulating healing and repair of different skeletal tissues. As expected, each of the two strategies have their own advantages and limitations (which we describe), especially when considering the diverse microenvironments of different skeletal tissues like bone, tendon/ligament, and cartilage/fibrocartilage. This paper also discusses stem/progenitor cells commonly used for repairing different skeletal tissues, and it lists ongoing clinical trials that have risen from the implementation of these cells and strategies. Lastly, we discuss our own thoughts on where the field is headed in the near future.

Orthoplastics in Periprosthetic Joint Infection of the Knee: Treatment Concept for Composite Soft-tissue Defect with Extensor Apparatus Deficiency

Introduction: Reconstruction of composite soft-tissue defects with extensor apparatus deficiency in patients with periprosthetic joint infection (PJI) of the knee is challenging. We present a single-centre multidisciplinary orthoplastic treatment concept based on a retrospective outcome analysis over 20 years. Methods and Results: One-hundred sixty patients had PJI after total knee arthroplasty. Plastic surgical reconstruction of a concomitant perigenicular soft-tissue defect was indicated in 47 patients. Of these, six presented with extensor apparatus deficiency. One patient underwent primary arthrodesis and five patients underwent reconstruction of the extensor apparatus. The principle to reconstruct missing tissue 'like with like' was thereby favoured: Two patients with a wide soft-tissue defect received a free anterolateral thigh flap with fascia lata; one patient with a smaller soft-tissue defect received a free sensate, extended lateral arm flap with triceps tendon; and two patients who did not qualify for free flap surgery received a pedicled medial sural artery perforator gastrocnemius flap. Despite good functional results 1 year later, long-term follow-up revealed that two patients had to undergo arthrodesis because of recurrent infection and one patient was lost to follow-up. Conclusion: These results show that PJI of the knee and extensor apparatus deficiency is a dreaded combination with a poor long-term outcome. Standardization of surgical techniques for a defined PJI problem and consensus on study variables may facilitate interinstitutional comparisons of outcome data, and hence, improvement of treatment concepts.

Intra-operative patellar fracture during chronic patellar tendon rupture reconstruction: salvage and prophylactic modified techniques

Management of chronic neglected patellar tendon rupture represents a challenging condition for the orthopedic surgeons to deal with due to many factors such as quadriceps muscle atrophy, superior migration of the patella, e.g., patella alta, peri-patellar adhesions and patellar tendon atrophy. Such difficulties might be further complicated by intra-operative patellar fracture during patellar tendon reconstruction. In the current article, the authors report (1) a salvage procedure for such devastating intra-operative complication, based on bypassing the patella and gaining the advantage of the quadriceps tendon for structural and functional restoration of the knee extensor mechanism, and (2) prophylactically a technical modification of patellar tendon reconstruction guarding against such inadvertent patellar fracture.

ALT flap with vascularized fascia lata for one-stage functional patellar tendon reconstruction

INTRODUCTION

Composite anterolateral thigh (ALT) flap with vascularized fascia lata can reconstitute patellar tendon integrity and knee soft tissue coverage in one stage. However, long-term evidence of outcomes is lacking. This work analyzes long-term functional results, compares subtotal and total reconstruction of patellar tendon, and assesses the respective function of the extensor apparatus.

PATIENTS AND METHODS

Outcomes of reconstruction using 10 ALT flaps in 9 patients (age range 21-87 years) were analyzed (mean follow-up 30 ± 6 months). Knee Society Scores, isometric knee extensor strength (M1-M5), and sensory recovery were evaluated, together with active range of motion and extensor lag of the reconstructed limb, compared to contralateral.

RESULTS

Ten flaps were used for tendon replacement in 9 patients. Eight (80%) free flaps and 2 (20%) propeller distally based flaps were used. Complications requiring the harvest of a second flap were seen in 2 patients. All patients could return to their daily activities without the use of walking supports. Mean active ROM was 94.4° with an extensor lag of 9.4°, without a significant difference between partial and total patellar tendon reconstruction. The mean knee and functional scores of the Knee Society were 81/100 and 77/100, respectively.

CONCLUSION

Composite ALT flap with fascia lata can satisfy the twofold needs of functional restoration and soft tissue coverage, thus ensuring stable results in total and subtotal knee extensor mechanism reconstruction. Distally based flaps should be carefully considered, as they lead to higher complication rates.

Treatment of a Neglected Patellar Tendon Rupture with a Modified Surgical Technique: Ipsilateral Semitendinosus Autograft Reconstruction with Suture Tape Augmentation

Patellar tendon ruptures are rare, but debilitating injuries are typically seen in young active males in the third and fourth decades of life. They can occur as a single acute injury or from repetitive microtrauma weakening the tendon. Patients typically present complaining of knee pain, swelling, and an inability to perform a straight leg raise. Most conventionally, these injuries are classified as acute (less than two weeks) or chronic (greater than two weeks) based upon the timing of presentation. In patients with patellar tendon ruptures and inability to perform a straight leg raise, patellar tendon repair is most often recommended. A subset of patients with chronic patellar tendon ruptures, however, presents several months after their initial injuries. These neglected patella tendon ruptures present a particularly challenging clinical scenario in which primary repair is often difficult or not possible. This case report describes a modification to an existing surgical technique for reconstructing the patellar tendon using an ipsilateral semitendinosus tendon autograft with suture tape augmentation.

Surgical Treatment for Failure of Repair of Patellar and Quadriceps Tendon Rupture With Ipsilateral Hamstring Tendon Graft

Tears of the patellar and quadriceps tendon are common in the active population, especially in athletes. At present, several techniques for surgical repair and reconstruction are available. When reruptures occur, a reconstruction is mandatory. In the present paper, we describe a surgical technique for patellar and quadriceps tendon reconstruction using ipsilateral hamstring autograft. After routine hamstring tendon harvesting, the tendon ends are prepared using a whip stitch. A transverse tunnel is drilled in the midportion of the patella, the hamstring graft is passed through the patella, and firmly secured to the patellar tunnel openings with sutures. The details of the technique are fully described. Autologous ipsilateral hamstring tendon grafts provide a secure sound means to manage these challenging injuries.

Ipsilateral hamstring tendon graft reconstruction for chronic patellar tendon ruptures: surgical technique

BACKGROUND

Patellar tendon chronic ruptures are more debated to manage that acute injuries as the patella tends to retract proximally (after 2 weeks), and surrounding soft tissues may make the repair more complicate.

PURPOSE

We propose a novel technique in which the patellar tendon is reconstructed using ipsilateral hamstring tendons. This surgical procedure implies to drill a single tunnel through the patella and another through the tibia to reduce the risk of bony breakage. In addition, the tendon is secured to the bone, at the tunnel exit points, by periostium sutures without requiring any additional surgery for hardware removal.

METHODS

We assessed 19 patients (16 men and 3 women) who underwent PT reconstruction at an average of 5.8 years (range, 4 to 7.8 years, SD: 3.5) from the index surgery. The mean age at surgery was 46 ± 9.2 years (range, 38-59 years).

RESULTS

All patients had a complete tear of the patellar tendon.

CONCLUSIONS

The main indication for this procedure is the reconstruction of the PT in patients with chronic rupture (>6 weeks) in which the tendon gap is greater than 2 centimeters and the scar tissues and degenerated tendon ends do not allow to juxtapose the tendon stumps to each other.

LEVEL OF EVIDENCE

Level IV.

Surgical repair of chronic patellar tendon rupture in total knee replacement with ipsilateral hamstring tendons

PURPOSE

Patellar tendon rupture is a serious complication of total knee arthroplasty (TKA). Its reconstruction in patients with chronic ruptures is technically demanding. This article reports the results of surgical reconstruction of neglected patellar tendon rupture in TKA using autologous hamstring tendons.

METHODS

Nine TKA patients (six women and three men) (mean age at index surgery 68 years) with chronic patellar tendon tears underwent reconstruction with ipsilateral hamstrings tendon, leaving the distal insertion in situ. The clinical diagnosis was supported by imaging (anterior-posterior and 30° flexion lateral radiographs). Insall-Salvati index, range of motion, and leg extension test were recorded preoperatively and at last follow-up. The modified Cincinnati rating system and the Kujala score were administered. The patients sustained the patellar tendon tear an average of 8 weeks before the procedure.

RESULTS

At final follow-up of 4 years (range 2-8 years), the median of extension lag was 5° (range 0°-15°; DS = 5). The median of post-operative Insall-Salvati index was 1.4 (range 1.3-1.8; SD = 0.15; p = 0.002) compared to the preoperative index of 1.7 (range 1.5-2.2; SD = 0.23). The mean modified Cincinnati and Kujala scores significantly increased compared with the preoperative ones (p < 0.01). At final follow-up, all patients were able to walk without brace or aids, and they were satisfied with the procedure.

CONCLUSION

Based on our retrospective study of nine patients, reconstruction of neglected patellar tendon rupture in TKA with autologous hamstring tendons is feasible and safe, and provides good functional recovery.

LEVEL OF EVIDENCE

Case series, Level IV.

Extensor tendon ruptures after total knee arthroplasty

Extensor tendon rupture is a rare but serious complication after total knee arthroplasty (TKA) that impairs active knee extension, thereby severely affecting knee function. Surgery is usually required. Surgical options range from simple suturing to allograft reconstruction of the entire extensor mechanism and include intermediate methods such as reconstruction using neighbouring tendons or muscles, synthetic ligament implantation, and partial allograft repair. Simple suturing carries a high failure rate and should therefore be routinely combined with tissue augmentation using a neighbouring tendon or a synthetic ligament. After allograft reconstruction, outcomes are variable and long-term complications common. Salvage procedures for managing the most severe cases after allograft failure involve reconstruction using gastrocnemius or vastus flaps. Regardless of the technique used, suturing must be performed under tension, with the knee fully extended, and rehabilitation must be conducted with great caution. Weaknesses of available case-series studies include small sample sizes, heterogeneity, and inadequate follow-up duration. All treatment options are associated with substantial failure rates. The patient should be informed of this fact and plans made for a salvage option. Here, the main techniques and their outcomes are discussed, and a therapeutic strategy is suggested.

Ipsilateral hamstring tendon graft reconstruction for chronic patellar tendon ruptures: average 5.8-year follow-up

BACKGROUND

Patellar tendon reconstruction is technically demanding and is indicated in patients with chronic ruptures (i.e., still present more than six weeks after injury). The purpose of this study was to assess the effectiveness of this procedure in patients with impaired function following patellar tendon rupture.

METHODS

Nineteen patients underwent autologous ipsilateral hamstring tendon graft reconstruction for management of a chronic patellar tendon rupture. The clinical diagnosis was supported by imaging radiographs and magnetic resonance imaging. The modified Cincinnati rating system questionnaire and the Kujala scoring questionnaire were administered preoperatively and at the last examination, an average follow-up of 5.8 years (range, four to 7.8 years) postoperatively. Thigh volume, cross-sectional area of the thigh (muscle and bone), and the maximum isometric voluntary contraction strength of the extensor apparatus of the knee were measured bilaterally in all nineteen patients.

RESULTS

At the last follow-up visit, knee flexion had increased from a mean of 110° preoperatively to a mean of 132° and extension lag had significantly decreased from 20° preoperatively to 3°; the mean modified Cincinnati and Kujala scores were notably improved. All patients had returned to ordinary daily activities. Fourteen of nineteen patients were very satisfied with the procedure, three were satisfied, one was moderately satisfied, and one was unsatisfied.

CONCLUSIONS

On the basis of our review of nineteen patients, hamstring tendon reconstruction of chronic patellar tendon rupture provided good functional recovery and return to preinjury daily activities.

Reconstruction and restoration of neglected ruptured patellar tendon using semitendinosus and gracilis tendons with preserved distal insertions: two case reports

Neglected rupture of the patellar tendon is rare but becomes more difficult to repair the longer it is left untreated. The most common rupture sites are the inferior pole of the patella and distal insertion. Proximal retraction of the patella and extensor mechanism adhesions makes the treatment more difficult than acute tendon rupture. We report two patients with neglected patellar tendon rupture treated by reconstruction and restoration using semitendinosus-gracilis (STG) tendons with preserved distal insertions. Preserved distal insertion provided sufficient blood supply to accelerate healing, while combined fixation with tension-reducing wire, offered the initial stability of the closed-loop sutured tendon. Both patients reacquired near normal strength and stability of the patellar tendon and restoration of function after operation and rehabilitation.

Exploring the application of stem cells in tendon repair and regeneration

PURPOSE

To conduct a systematic review of the current evidence for the effects of stem cells on tendon healing in preclinical studies and human studies.

METHODS

A systematic search of the PubMed, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Cochrane, and Embase databases was performed for stem cells and tendons with their associated terminology. Data validity was assessed, and data were collected on the outcomes of trials.

RESULTS

A total of 27 preclinical studies and 5 clinical studies met the inclusion criteria. Preclinical studies have shown that stem cells are able to survive and differentiate into tendon cells when placed into a new tendon environment, leading to regeneration and biomechanical benefit to the tendon. Studies have been reported showing that stem cell therapy can be enhanced by molecular signaling adjunct, mechanical stimulation of cells, and the use of augmentation delivery devices. Studies have also shown alternatives to the standard method of bone marrow-derived mesenchymal stem cell therapy. Of the 5 human studies, only 1 was a randomized controlled trial, which showed that skin-derived tendon cells had a greater clinical benefit than autologous plasma. One cohort study showed the benefit of stem cells in rotator cuff tears and another in lateral epicondylitis. Two of the human studies showed how stem cells were successfully extracted from the humerus and, when tagged with insulin, became tendon cells.

CONCLUSIONS

The current evidence shows that stem cells can have a positive effect on tendon healing. This is most likely because stem cells have regeneration potential, producing tissue that is similar to the preinjury state, but the results can be variable. The use of adjuncts such as molecular signaling, mechanical stimulation, and augmentation devices can potentially enhance stem cell therapy. Initial clinical trials are promising, with adjuncts for stem cell therapy in development.

Stem cell applications in tendon disorders: a clinical perspective

Tendon injuries are a common cause of morbidity and a significant health burden on society. Tendons are structural tissues connecting muscle to bone and are prone to tearing and tendinopathy, an overuse or degenerative condition that is characterized by failed healing and cellular depletion. Current treatments, for tendon tear are conservative, surgical repair or surgical scaffold reconstruction. Tendinopathy is treated by exercises, injection therapies, shock wave treatments or surgical tendon debridement. However, tendons usually heal with fibrosis and scar tissue, which has suboptimal tensile strength and is prone to reinjury, resulting in lifestyle changes with activity restriction. Preclinical studies show that cell therapies have the potential to regenerate rather than repair tendon tissue, a process termed tenogenesis. A number of different cell lines, with varying degrees of differentiation, have being evaluated including stem cells, tendon derived cells and dermal fibroblasts. Even though cellular therapies offer some potential in treating tendon disorders, there have been few published clinical trials to determine the ideal cell source, the number of cells to administer, or the optimal bioscaffold for clinical use.

What we should know before using tissue engineering techniques to repair injured tendons: a developmental biology perspective

Tendons connect muscles to bones, and serve as the transmitters of force that allow all the movements of the body. Tenocytes are the basic cellular units of tendons, and produce the collagens that form the hierarchical fiber system of the tendon. Tendon injuries are common, and difficult to repair, particularly in the case of the insertion of tendon into bone. Successful attempts at cell-based repair therapies will require an understanding of the normal development of tendon tissues, including their differentiated regions such as the fibrous mid-section and fibrocartilaginous insertion site. Many genes are known to be involved in the formation of tendon. However, their functional roles in tendon development have not been fully characterized. Tissue engineers have attempted to generate functional tendon tissue in vitro. However, a lack of knowledge of normal tendon development has hampered these efforts. Here we review studies focusing on the developmental mechanisms of tendon development, and discuss the potential applications of a molecular understanding of tendon development to the treatment of tendon injuries.

Reconstruction of knee joint soft tissue and patellar tendon defects using a composite anterolateral thigh flap with vascularized fascia lata

Reconstruction of a complex knee trauma with knee joint exposure and composite soft tissue and patellar tendon deficiency remains a challenging task. Multiple-stage reconstruction is time-consuming and produces considerable suffering for patients. Early mobilization following knee reconstruction has achieved good outcomes. Herein, we reported one-stage reconstruction with an ALT myocutaneous flap with vascularized fascia lata was utilized for one patient with a large complex knee joint soft tissue defect, and segmental deficiency of the patellar tendon. The fascia lata sheet was rolled to mimic a patellar tendon. The exposed knee joint was obturated by the vastus lateralis muscle of the ALT myocutaneous flap. The skin and soft tissue defect was reconstructed using the skin paddle of the ALT flap. The patient's postoperative course was uneventful. An MRI examination demonstrated good continuity of the reconstructed patellar tendon. The active ROM of the injured knee reached 100 degrees (extension deficiency 20 degrees and flexion 120 degrees ) at 5 years. Objective functional assessment of the patella-femoral joint utilized a kinetic communicator machine (Kin-Com 500H, Chattecx, Chattanooga, TN, USA) revealed still mild extension insufficiency. However, the patient reported that he was able to perform normal daily activities without difficulty at 5-year follow-up.

Vastus Medialis Muscle Flap and Hemi V-Y Skin Flap for Knee Extensor and Soft Tissue Reconstruction

Simultaneous reconstruction of extensor mechanism and skin defect of the knee joint is a difficult problem. We present a case of a 55-year-old man with loss of patella and 9 x 6 cm skin defect after total patellectomy for infected open patellar fracture. Vastus medialis muscle flap and hemi V-Y skin flap were elevated. Vastus medialis muscle flap was advanced and sutured to the remaining patellar tendon. Hemi V-Y skin flap covered the skin defect. The wound healed uneventfully. After a follow-up period of 30 months, active range of motion of the knee joint is 0-120 degrees, and extension strength of the knee joint is [4] in a manual muscle test. He can stand on his right leg without any assistance. The combination of vastus medialis flap and hemi V-Y skin flap is a valuable option in knee reconstruction after total patellectomy.

Surgical treatment options for patella tendon rupture, part II: chronic

Patella tendon rupture is a debilitating injury that often occurs in the setting of preexisting tendon degeneration. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In the setting of a chronic rupture, augmentation with hamstring tendons or allograft reconstruction generally is necessary. Patients who undergo delayed repair are at risk for a compromised result secondary to loss of full knee flexion and decreased quadriceps strength, although a functional extensor mechanism is likely to be reestablished. Overall the results of chronic repair are less satisfactory than the acute repair, but still provide an extensor mechanism for the patient and thus provide function.

Surgical treatment options for patella tendon rupture, Part I: Acute

Patella tendon rupture is a debilitating injury. Prompt diagnosis and treatment is essential to prevent retraction of the patella with subsequent adhesions and quadriceps contractures. In a young patient with an acute rupture, primary repair usually is possible with various methods described to protect the repair. In acute injuries with inadequate tissue, augmentation with hamstring tendons or allograft generally is necessary. Because of the different types of rupture and the possibility for poor quality tissue, the surgeon should always be prepared to combine different techniques to obtain tthe best repair. Continuous passive motion generally can be initiated early with a secure repair. In patients with a patella tendon ruptured that is promptly diagnosed, securely repaired, and followed closely through their rehabilitation, good results can be expected.

Reconstruction of ruptured patellar tendon after total knee arthroplasty: a case report and a description of an alternative fixation method

Patellar tendon rupture after total knee arthroplasty is a rare, but often catastrophic complication. Many different reconstruction techniques of patellar tendon rupture have been described with variable and often discouraging results. A case report with patellar tendon rupture after a total knee arthroplasty is presented. Also, an alternative surgical technique of reconstruction of the patellar tendon using a semitendinosus-gracilis (STG) graft with an interference screw and a staple fixation enabling an immediate mobilization is described.

Extended medial gastrocnemius rotational flap for treatment of chronic knee extensor mechanism deficiency in patients with and without total knee arthroplasty

Nine patients with chronic extensor mechanism disruption were treated with an extended medial gastrocnemius rotational flap reconstruction of the extensor mechanism. Seven patients previously had total knee arthroplasty and two patients had chronic infection of nonreplaced, native knees. Four patients previously had failed Achilles' tendon allograft reconstruction after total knee arthroplasty and two were complicated by infection. Infected arthroplasty patients had a staged procedure with placement of an antibiotic spacer after debridement and extended medial gastrocnemius rotational flap, followed by total knee arthroplasty replant 8 weeks later. The four infected arthroplasty patients had medical comorbidities that included a patient with HIV and hemophilia, and two with diabetes mellitus. Another patient with rheumatoid arthritis was severely malnourished as a result of dumping syndrome. Of the four patients treated by this two-stage procedure, one died in the early postoperative period from chronic medical issues after the second stage and another patient elected to have above-knee amputation after the first stage because of severe reflex sympathetic dystrophy. The final group of seven patients was studied at a mean followup of 21 months (range, 7-31 months), the average extensor lag was 13.5 degrees (range, 0-50 degrees ), and the average range of motion was 2 degrees to 93 degrees . The two patients with nonreplaced, native knees had extensor lags of 30 degrees and 10 degrees . All patients were able to regain sufficient extensor mechanism strength to return to independent ambulation, and all infections resolved after treatment. Two patients were able to ascend stairs foot over foot without support. In addition to the patient who had amputation, the other complication involved a wound breakdown that required a free flap at 13 months in a patient who had a failed Achilles' tendon allograft reconstruction after takedown of a knee fusion. Medial gastrocnemius flap reconstruction can provide successful salvage of a failed extensor mechanism allograft or an alternative to allograft reconstruction in patients with poor soft tissue coverage, previous infection, or a compromised immune system.

Reconstruction of a ruptured patellar tendon with achilles tendon allograft following total knee arthroplasty

BACKGROUND

Rupture of the patellar tendon after total knee arthroplasty is a rare and debilitating complication. Proper surgical management of this condition remains controversial. The purpose of this study was to review the results of reconstruction of a ruptured patellar tendon with an Achilles tendon allograft following total knee arthroplasty.

METHODS

We reviewed our experience with the use of a fresh-frozen Achilles tendon allograft with an attached calcaneal bone graft to restore extensor function in nine patients with patellar tendon rupture following total knee arthroplasty (five primary and four revision). All patients were examined clinically and radiographically at an average of twenty-eight months.

RESULTS

The average knee and functional scores improved from 26 and 14 points, respectively, before the surgery to 81 and 53 points after the surgery. The average extensor lag decreased from 44 degrees preoperatively to 3 degrees postoperatively, and the average range of motion of the knee increased from 88 degrees to 107 degrees. Two grafts failed in the early postoperative period. Both were repaired successfully. Radiographs showed an average proximal patellar migration of 17.8 mm, which did not appear to affect extensor function.

CONCLUSIONS

This short-term follow-up study showed that once an Achilles allograft has healed, it can serve as a reliable reconstruction of a ruptured patellar tendon following total knee arthroplasty. This technique may be particularly suited for patients in whom the extensor mechanism was compromised by multiple prior operations. Continued follow-up is necessary to determine the long-term durability of these results.