Arthroscopic management of arthrofibrosis of the knee, including infrapatellar contraction syndrome

Clinical Outcomes After Arthroscopic Release of Patellofemoral Arthrofibrosis in Patients With Prior Anterior Cruciate Ligament Reconstruction

PURPOSE

The purpose of this study was to review our results of arthroscopic release in patients diagnosed with refractory patellofemoral arthrofibrosis (PFA) after having undergone anterior cruciate ligament (ACL) reconstruction.

METHODS

From 2006 to 2016, all patients who underwent arthroscopic release for refractory PFA after ACL reconstruction were reviewed retrospectively. All patients then completed surveys containing the International Knee Documentation Committee (IKDC) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and were asked 2 subjective questions. Patients included in the study exhibited at least one finding of PFA and failed conservative treatment for at least 3 months. Included patients also had a minimum of 12 months of postoperative follow-up after PFA release. Patients who underwent any other concomitant surgery in the same operative setting as arthroscopic release for PFA were excluded from the study.

RESULTS

Thirty-two patients were included in the study. The mean age was 32.8 years (range, 19-58 years) with an average follow-up of 43.6 months (range, 16-98 months). There was a statistically significant increase preoperatively to postoperatively in the IKDC score from 49.6 to 69.4 (P < .00001), and 16 of 32 patients (50%) achieved a minimal clinically important difference (MCID). WOMAC scores also significantly increased from 74 to 85.3 (P < .00001), with 15 of 32 patients (47%) achieving MCID. Thirty-one patients (97%) reported that the procedure helped, and 25 patients (78%) said they would have the procedure again.

CONCLUSIONS

Arthroscopic release, consisting of an extended lateral release, debridement of the notch/fat pad, and manual manipulation of the patella, results in significant increases in validated outcome measures and is well tolerated by patients.

LEVEL OF EVIDENCE

Level IV, case series.

Presentation and management of arthrofibrosis of the knee: A case report

STUDY DESIGN

Case report.

BACKGROUND

Arthrofibrosis is a debilitating condition that results in pain, decreased range of motion, and decreased function. Although surgical management of arthrofibrosis has been well described in the literature, rehabilitation of the arthrofibrotic knee is less well described.

CASE DESCRIPTION

A 28-year-old female presented with swelling, pain, and decreased strength, range of motion, patellar mobility, and function following an exploratory arthroscopy of her left knee. After failed conservative management, the patient underwent two additional surgeries to remove scar tissue. Following each surgery, the emphasis was on decreasing inflammation and maintaining patellar mobility while increasing joint range of motion and strength. Therapy progression was determined by the presence or absence of inflammatory signs. The second scar tissue removal surgery resulted in a femoral neuropathy that further complicated the rehabilitation process.

OUTCOMES

At 3-year follow-up, the patient continued to present with decreased range of motion and strength compared to the uninvolved limb, but had returned to a modified running program and reported pain no longer limited her ability to participate in activities of daily living.

DISCUSSION

This case report highlights the importance of recognizing that arthrofibrosis may result following a minor knee surgery and with minimal range of motion loss. Additional complications also may result during arthrofibrosis treatment. Progressing rehabilitation based on the inflammatory response may decrease the likelihood of additional scar tissue formation and potentially improve the outcome for the patient.

Association of fibrosis in the infrapatellar fat pad and degenerative cartilage change of patellofemoral joint after anterior cruciate ligament reconstruction

BACKGROUND

The purpose of this study was to evaluate the prevalence and risk factor of cartilage degeneration of the patellofemoral joint (PFJ) that was diagnosed by second-look arthroscopy.

METHODS

One-hundred and seven patients who underwent ACL reconstruction were evaluated by preoperative MRI, postoperative MRI and second-look arthroscopy. Severity of infrapatellar fat pad (IPFP) fibrosis was evaluated by MRI at an average of 26months after ACL reconstruction. Cartilage degeneration was assessed by second-look arthroscopy at 29months.

RESULTS

Twenty-five patients (24.0%) showed cartilage degeneration of the PFJ in second-look arthroscopy. Patients were divided into three groups according to severity of IPFP fibrosis of postoperative MRI (i.e. Group A, focal and incomplete band fibrosis, n=69; Group B, complete band fibrosis, n=31; and Group C, diffuse and infiltrated fibrosis, n=7). Cartilage degeneration of the PFJ was significantly worsened with more fibrosis formation of the IPFP (P<0.001). Other factors for instabilities (BMI, age, concomitant meniscal procedure, time from injury to reconstruction, severity of IPFP fibrosis at preoperative MRI and clinical scores) were not correlated with cartilage degeneration of the PFJ. The multivariate logistic regression analysis of degeneration of the PFJ after ACL reconstruction identified more severe fibrosis tissue formation of the IPFP and initial cartilage defect as significant predictors.

CONCLUSIONS

More extensive fibrosis of the IPFP and initial cartilage defect may be related to further degenerative changes of the PFJ. Other factors did not affect cartilage degeneration of the PFJ, although the muscle strength, the individual activity level or the rehabilitation protocol was not evaluated in the short-term follow-up period.

Joint Contractures Resulting From Prolonged Immobilization: Etiology, Prevention, and Management

Patients who are immobilized for a prolonged period are at risk for developing joint contractures, which often affect functional outcomes. Nonsurgical interventions are useful for preventing joint contractures. However, once contractures develop, these interventions frequently fail to restore function over the long term. To increase the rehabilitation potential of an extremity with refractory function-limiting contractures, surgery is often required.

Nonligamentous Soft Tissue Pathology About the Knee: A Review

Knee pain is one of the most frequent complaints evaluated by orthopedic surgeons. It encompasses a broad range of pathology and can present in a variety of ways. Most of this pain can be attributed to essential structures of the knee, including the menisci, cruciate or collateral ligaments, and articular cartilage. However, there are underrecognized structures in and around the knee that can frequently be a cause of knee pathology and pain. Knee pain stemming from these structures may be missed or incorrectly diagnosed, and these patients often present for second and third opinions because of failure to diagnose and treat the underlying pathology. The synovial plica, suprapatellar pouch, lateral retinaculum, infrapatellar fat pad, and infrapatellar branch of the saphenous nerve are less common but still significant causes of knee pain. Although initial treatment involves various nonoperative modalities, operative treatment is often warranted. Operative and nonoperative management of these soft tissue structures may occur in isolation or with concomitant procedures, including knee ligament reconstruction, total knee arthroplasty, tibial tuberosity osteotomy, or lysis of adhesions. With proper recognition of the role of these structures in knee pain, the orthopedic surgeon can offer a valuable primary or adjunctive treatment option for patients with knee pain, especially those without localizing signs of meniscal, ligamentous, or cartilage damage.

Fibrosis is a common outcome following total knee arthroplasty

Total knee arthroplasty (TKA) is one of the most successful orthopaedic procedures that alleviates pain and restores function in patients with degenerative knee joint diseases. Arthrofibrosis, abnormal scarring in which dense fibrous tissue prevents normal range of motion, develops in ~3–10% of TKA patients. No prophylactic intervention is available and treatment is restricted to aggressive physiotherapy or revision surgery. Tissue was collected from patients undergoing primary (n = 30) or revision (n = 27) TKA. Revision patients were stratified as non-arthrofibrotic and arthrofibrotic. Tissue was macroscopically and histologically compared to improve our understanding of the pathophysiology of arthrofibrosis. Macroscopically, tissue from primary TKA presents as homogenous, fatty tissue whereas tissue from revision TKA presents as dense, pigmented tissue. Histologically, there was dramatic tissue remodelling, increased collagen deposition and increased (myo)fibroblast staining in tissue from revision TKA. Significantly, tissue architecture was similar between revision patients regardless of clinically diagnosis. There are significant differences in architecture and composition of tissue from revision TKA over primary TKA. Surprisingly, whether revision TKA were clinically diagnosed as arthrofibrotic or non-arthrofibrotic there were still significant differences in fibrotic markers compared to primary TKA suggesting an ongoing fibrotic process in all revision knees.

Evaluation, Treatment, and Rehabilitation Implications of the Infrapatellar Fat Pad

Context:

The infrapatellar fat pad (IFP) is in the anterior knee compartment and may be a major pain generator.

Evidence Acquisition:

A PubMed database search using the terms Hoffas fat pad, anterior interval, and infrapatellar fat pad was performed from the years 1970 to 2015.

Study Design:

Clinical review.

Level of Evidence:

Level 5.

Results:

Limited research exists examining the role of the IFP in relation to potential treatment and rehabilitation implications.

Conclusions:

Alterations in IFP mobility, whether the result of postsurgical scarring or faulty movement patterns, result in pain and disability in a variety of patient populations. The majority of treatment approaches are driven by the surgical technique.

Adhesive capsulitis of the knee

The authors describe the case of a 42-year-old woman presenting with significant knee pain and disability. Her imaging findings using contrast MR imaging and FDG PET/CT suggested adhesive capsulitis, which was confirmed by arthroscopy, histology, and the clinical outcome.

Perioperative rehabilitation using a knee extension device and arthroscopic debridement in the treatment of arthrofibrosis

BACKGROUND

Arthrofibrosis is a postoperative complication of intra-articular knee surgery that can be difficult to treat. Evidence suggests that maximizing knee range of motion may improve outcomes in patients with arthrofibrosis who undergo arthroscopic debridement.

HYPOTHESIS

Patients who achieve greater knee range of motion will have better subjective scores.

STUDY DESIGN

Retrospective case series analysis.

METHODS

A review of records was performed for 33 patients with arthrofibrosis who underwent knee arthroscopy and scar resection coupled with perioperative rehabilitation to maximize knee range of motion. Patient demographics and preoperative and postoperative range of motion measurements were extracted from the records. The International Knee Documentation Committee (IKDC) Subjective Knee Form was administered to assess pain, activity, and knee function. Patients performed a preoperative and postoperative rehabilitation program utilizing a knee extension device to maximize knee extension.

RESULTS

According to the IKDC range of motion criteria, 27 of 33 patients achieved normal knee extension, and 14 of 33 achieved normal knee flexion at a mean of 8.6 months after surgery. Patients with normal knee motion had a mean IKDC Subjective Knee Form score of 72.6 ± 13.6, which was significantly higher than patients who did not achieve normal motion (P = .04). Overall, mean IKDC Subjective Knee Form scores improved from 45.3 ± 16.7 preoperatively to 67.1 ± 18.0 postoperatively (P < .01) at a mean of 14.7 months after surgery.

CONCLUSIONS

Perioperative rehabilitation that emphasizes restoration of normal knee range of motion appears to improve outcomes in patients with arthrofibrosis who undergo arthroscopic scar resection. In support of our hypothesis, patients who achieved greater knee range of motion had better subjective knee scores.

Evaluation and treatment of disorders of the infrapatellar fat pad

The infrapatellar fat pad (IFP), also known as Hoffa's fat pad, is an intracapsular, extrasynovial structure that fills the anterior knee compartment, and is richly vascularized and innervated. Its degree of innervation, the proportion of substance-P-containing fibres and close relationship to its posterior synovial lining implicates IFP pathologies as a source of infrapatellar knee pain. Though the precise function of the IFP is unknown, studies have shown that it may play a role in the biomechanics of the knee or act as a store for reparative cells after injury. Inflammation and fibrosis within the IFP, caused by trauma and/or surgery can lead to a variety of arthrofibrotic lesions including Hoffa's disease, anterior interval scarring and infrapatellar contracture syndrome. Lesions or mass-like abnormalities rarely occur within the IFP, but their classification can be narrowed down by radiographical appearance. Clinically, patients with IFP pathology present with burning or aching infrapatellar anterior knee pain that can often be reproduced on physical exam with manoeuvres designed to produce impingement. Sagittal MRI is the most common imaging technique used to assess IFP pathology including fibrosis, inflammation, oedema, and mass-like lesions. IFP pathology is often successfully managed with physical therapy. Passive taping is used to unload or shorten an inflamed IFP, and closed chain quadriceps exercises can improve lower limb control and patellar congruence. Training of the gluteus medius and stretching the anterior hip may help to decrease internal rotation of the hip and valgus force at the knee. Gait training and avoiding hyperextension can also be used for long-term management. Injections within the IFP of local anaesthetic plus corticosteroids and IFP ablation with ultrasound guided alcohol injections have been successfully explored as treatments for IFP pain. IFP pathology refractory to physical therapy can be approached through a variety of operative treatments. Arthroscopic partial resection for IFP impingement and Hoffa's disease has showed favourable results; however, total excision of the IFP performed concomitantly with total knee arthroplasty (TKA) resulted in worse results when compared with TKA alone. Arthroscopic debridement of IFP fibrosis has been successfully used to treat extension block following anterior cruciate ligament reconstruction, and arthroscopic anterior interval release has been an effective treatment for pain associated with anterior interval scarring. Arthroscopic resection of infrapatellar plicae and denervation of the inferior pole of the patella have also been shown to be effective treatments for refractory infrapatellar pain.

Arthroscopic dorsal capsular release in the wrist: a new technique

Wrist stiffness is a multifactorial condition that is debilitating for those which it affects. Although good results have been achieved in the past with aggressive physiotherapy and splinting regimens, however, there are some cases that remain refractory to this treatment. In those cases that are caused primarily by arthrofibrosis, arthroscopic surgical release of the capsule is another treatment option. Arthroscopic release of the volar wrist capsule has been previously described. The authors describe this new technique for arthroscopic dorsal capsular release using an intracapsular nylon tape to afford protection to the extensor tendons. They believe that the procedure is relatively safe with a low complication rate as well as good patient outcomes. Although the cohort of patients in whom this procedure is indicated is likely to be small, we feel that it gives the upper-limb surgeon another option for managing this often difficult problem.

Arthroscopic posteromedial capsular release for knee flexion contractures

Extension deficits of the knee can cause functional limitations in patients after knee surgery or injury. Most frequently, they are treated with manipulations, arthroscopic anterior compartment debridements, or open posterior capsular releases once nonoperative treatment fails. However, an arthroscopic posteromedial capsular release to manage flexion deficits has yet to be studied comprehensively. Arthroscopic posteromedial capsular releases of the knee can result in improved knee motion postoperatively. An arthroscopic posteromedial capsular release involves sectioning the posteromedial capsule at its meniscofemoral portion, midway between its femoral attachment and its posterior horn medial meniscus junction. A review of 15 patients who underwent this operation was performed. Passive knee extension and flexion was measured in patients in the supine position using a goniometer at preoperative evaluations, under anesthesia prior to and immediately after the posteromedial capsular release, and at postoperative follow-up evaluations. The average time from the arthroscopic posteromedial capsular release to the final postoperative follow-up was 24.1 months. Preoperative knee extension averaged 14.7 degrees in 15 patients. The average immediate postoperative knee extension averaged -0.9 degrees. At the final postoperative follow-up, knee extension averaged 0.7 degrees. Overall knee motion improved from an average are of motion of 101.6 degrees-129.4 degrees. Arthroscopic posteromedial capsular releases and the concurrent postoperative rehabilitation program were effective in the treatment of knee extension deficits. The encouraging results of this study compare well to data presented in open posterior capsular release studies. We believe that arthroscopic posteromedial capsular releases are an effective means to address symptomatic knee extension deficits.

Wrist arthrofibrosis

Wrist arthrofibrosis is a condition of decreased range of wrist motion due to intrinsic adhesions and extrinsic contracture. It is clinically characterized by restricted wrist range of motion, pain, swelling, and a plateau in improvement after at least 6 months of intensive physiotherapy. Other conditions must be excluded, such as articular incongruity, arthritis, spasticity, skin and subcutaneous scarring, and loose bodies. We have devised a classification system based on pathologic anatomic location, where Type I represents intrinsic adhesions, and Type II represents extrinsic contracture. The types are subdivided according to where the pathology is present. The operative approach should be wrist arthroscopy for Types IA (radiocarpal adhesions) and IB (midcarpal adhesions) where intraarticular adhesions are present. Types IC (distal radioulnar joint adhesions) and II C (distal radioulnar joint capsular contracture) are best approached in an open manner where dorsal and palmar capsulectomies of the distal radioulnar joint are performed. For Types IIA, B, and D (dorsal, palmar, and combination extrinsic contracture, respectively), both open and arthroscopic methods are described.

A new treatment strategy for severe arthrofibrosis of the knee. A review of twenty-two cases

BACKGROUND

To reduce the morbidity of traditional quadricepsplasty for the treatment of severe arthrofibrosis of the knee, we instituted a treatment regimen consisting of an initial extra-articular mini-invasive quadricepsplasty and subsequent intra-articular arthroscopic lysis of adhesions during the same anesthesia session. The purpose of the present study was to determine the results of this technique.

METHODS

From 1998 to 2001, twenty-two patients with severely arthrofibrotic knees were managed with this operative technique. The mean age of the patients at the time of the operation was thirty-seven years. After a mean duration of follow-up of forty-four months (minimum, twenty-four months), all patients were evaluated according to the criteria of Judet and The Hospital for Special Surgery knee-rating system.

RESULTS

The average maximum degree of flexion increased from 27 degrees preoperatively to 115 degrees at the time of the most recent follow-up (p < 0.001). According to the criteria of Judet, the result was excellent for sixteen knees, good for five, and fair for one. The average Hospital for Special Surgery knee score improved from 74 points preoperatively to 94 points at the time of the most recent follow-up (p < 0.001). A superficial wound infection occurred in one patient. Only one patient had a persistent 15 degrees extension lag.

CONCLUSIONS

This mini-invasive operation for the severely arthrofibrotic knee can be used to increase the range of motion and enhance functional outcome.

Die Arthrolyse bei chronischen Beugedefiziten des Kniegelenks

AIM AND METHOD

Limitations to the range of motion of the knee reduce knee function and life quality. Flexion deficits inhibit using stairs and shoe closure, and may cause social deprivation. We present a pathophysiological concept of arthrolysis of the knee for flexion deficit. Our concept divides into intra- and extra-articular factors involving knee stiffness. Extra-articular problems can be located proximally in the quadriceps mechanism and distally in the patellar tendon.

RESULTS

The main proximal factor is fibrosis of the vastus intermedius muscle (MVI) which is treated by MVI-resection; the main distal factor is shortening of the patellar tendon which is treated by z-plasty of the this tendon or transposition of the tibial tuberosity. Intra-articular factors are adhesions and fat pad fibrosis. These conditions can be treated by arthroscopic or limited open arthrolysis and eventually z-plasty of the retinacula.

CONCLUSION

A strict postoperative protocol is obligatory for pain control and physiotherapy. In 19 cases treated with this algorithm there was a mean flexion gain of 26 degrees. The AOSSM subjective outcome score was excellent in ten and good in seven cases after a mean follow-up of 8.2 months. This treatment protocol allows improvement in flexion, even in difficult revision cases.

Anterior cruciate ligament revision reconstruction: results using a quadriceps tendon-patellar bone autograft

BACKGROUND

The quadriceps tendon is a viable graft source for revision anterior cruciate ligament reconstruction.

PURPOSE

To determine the functional results and graft failure rates in knees in which the patellar tendon had been previously harvested or was unavailable, expanded tunnels precluded the use of a semitendinosus-gracilis graft, or patients requested autogenous tissues instead of allografts for revision reconstruction.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

The authors observed 21 patients for a mean of 49 months postoperatively after revision anterior cruciate ligament reconstruction with a quadriceps tendon graft. The results were determined by KT-2000 arthrometer testing, the Cincinnati Knee Rating System, and the International Knee Documentation Committee Rating System. Fifteen knees required a concurrent procedure, including reconstruction of posterolateral structures in 5 knees, meniscal repairs in 5 knees, and high tibial osteotomy in 2 knees.

RESULTS

Significant improvements occurred in symptoms (P < .0001), daily activities (P < .05), sports activities (P < .01), and the overall rating scores (P < .0001). Eighteen patients rated their knee condition as improved. Total mean anterior-posterior displacements decreased from 8.4 +/- 3.1 mm preoperatively to 2.0 +/- 2.3 mm at follow-up (P < .001). On the International Knee Documentation Committee knee ligament rating, 17 knees were graded as normal or nearly normal, 3 were graded as abnormal, and 1 was graded as severely abnormal.

CONCLUSION

The revision operation provided reasonable results in this group of complex knees. However, the functional and overall results were inferior to those reported for primary anterior cruciate ligament reconstruction. Many knees (90%) had compounding problems of articular cartilage damage, meniscectomy, varus malalignment, or additional ligamentous injury that most likely affected the results.

Arthroscopic treatment of the arthrofibrotic knee

The management of motion loss of the knee is challenging. A clear understanding of the pathoanatomic causes of motion loss is necessary to establish a careful and rational approach to treatment. Early recognition and physical therapy are effective for the majority of patients, but when these conservative measures fail, operative intervention is indicated. The purpose of this article is to outline a comprehensive approach to the arthroscopic evaluation and treatment of the arthrofibrotic knee. This technique is designed to allow the surgeon to systematically address the numerous causes of motion loss of the knee.

Arthroscopic operations in joint tuberculosis

We assessed the usefulness of arthroscopy in bone and joint tuberculosis (11 knees, 1 elbow and 1 ankle). In all 11 patients with knee joint involvement the arthroscopic operation were successful with a significant improvement in the range of motion (P=0.007) and knee score (P=0.003). There were no cases of reactivation or recurrence during a follow-up period of 15-42 months. In contrast, in the two patients with ankle or elbow joint involvement and bone destruction, arthroscopy had to be converted to open operation. Minor trauma, a short hospitalization time and a short post-operative rehabilitation period combined with good cosmetic and clinical results favor the use of the arthroscopic technology in the surgical treatment of tuberculous arthritis of the knee.

Multipotent stromal cells derived from the infrapatellar fat pad of the knee

Tissue engineering approaches for promoting the repair of skeletal tissues have focused on cell-based therapies involving multipotent stromal cells. Recent studies have identified such cells in several tissues in the adult human, including skin, muscle, bone marrow, and subcutaneous fat. This study examined the hypothesis that the infrapatellar fat pad of the adult knee contains progenitor cells that have the ability to differentiate into chondrocytes, osteoblasts, or adipocytes under appropriate culture conditions. Cells isolated from the fat pad stroma had a profile of cell-surface molecules similar but not identical to that of bone marrow-derived mesenchymal stem cells. Using defined culture conditions, fat pad-derived stromal cells were induced to differentiate cells with phenotypic characteristics of: (1) chondrocytes, synthesizing cartilage matrix molecules; (2) adipocytes, producing lipid vacuoles and leptin; or (3) osteoblasts, forming mineralized tissue. The culture conditions also modulated the expression of characteristic gene markers for each lineage. This study supports the hypothesis that multipotent stromal cells are present in many connective tissues in the adult human. Given its location and accessibility, the fat pad may prove to be a potential source of progenitor cells for musculoskeletal tissue engineering.

Decreased range of motion following acute versus chronic anterior cruciate ligament reconstruction

Eighty patients with acute anterior cruciate ligament (ACL) reconstruction were compared to 80 patients with chronic ACL reconstruction. Before reconstruction, all patients had 0 degrees-120 degrees active motion, performed a straight leg raise without loss of extension, and demonstrated good quadriceps control. At 3 months, 4 acute patients had decreased range of motion (<10 degrees-120 degrees), but none at 6 or 12 months, and did not require repeat surgery. One chronic patient had decreased range of motion at 3 and 6 months and 1 patient had decreased range of motion at 1 year; both patients required operative intervention. Using these specific preoperative criteria, no increased incidence of decreased range of motion was found when an ACL reconstruction was performed within 3 weeks of injury.

Motion loss after ligament injuries to the knee. Part II: prevention and treatment

This is the second part of a two-part review on motion problems after ligament injuries to the knee. The first part, published in the September/October 2001 issue, discussed normal and abnormal knee motion, terminology, risk factors, and pathoanatomy. The purpose of this article is to review current concepts on prevention and treatment of motion problems, summarizing the recent and pertinent studies that discuss this complicated clinical problem. The first part of this article will discuss the different classification schemes that have been published on motion loss of the knee. Prevention strategies will be discussed next, followed by early recognition. Finally, a discussion of the various treatment options and published results will be presented in detail, together with the authors' nine-step systematic surgical approach to the stiff knee.

Motion loss after ligament injuries to the knee. Part I: causes

Motion loss continues to be a difficult complication after ligament injury and surgery to the knee. A better understanding of the pathoanatomic causes of motion loss can lead to improved prevention and treatment strategies. When motion loss does occur, early recognition and appropriate treatment can be expected to restore motion and improve function in most patients. Treatment options, although varied, should improve outcome when implemented appropriately. This article is composed of two parts. The first part reviews the current concepts on definitions, incidence, and causes of motion loss. In the second part, to be published later, current strategies on prevention and treatment of motion loss after ligament injury to the knee are reviewed. Emphasis is placed on risk factors and prevention as well as on diagnosis and treatment. The article summarizes the latest information from the basic sciences as well as clinical studies on the problem of motion loss of the knee and attempts to provide a rational approach to these difficult clinical problems.

A symptomatic cyclops lesion 4 years after anterior cruciate ligament reconstruction

The cyclops lesion is a fibrous nodule with central granulation tissue located anterolateral to the tibial tunnel after intra-articular reconstruction of the anterior cruciate ligament (ACL) that has been shown to be a cause of failure to regain full extension in the early postoperative period. We present the case of a 23-year-old woman who had undergone arthroscopic ACL reconstruction with a patellar tendon autograft 4 years prior to presentation. Following her reconstruction, she regained full range of motion and returned to collegiate cheerleading. At presentation, she complained of a gradual loss of full extension and joint-line pain with terminal extension. On examination, her graft was stable and she lacked 3 degrees of extension. Magnetic resonance imaging documented a 1-cm mass of low signal intensity immediately anterior to the ACL graft within the intercondylar notch. At arthroscopy, a large amount of thick, immobile scar tissue was found immediately anterior to the ACL, consistent with a cyclops lesion. The lesion was debrided and the patient did well postoperatively. Patients who present with delayed-onset loss of extension after ACL reconstruction should undergo careful evaluation including radiographs and magnetic resonance imaging. If a cyclops lesion is diagnosed, arthroscopic resection should be undertaken.

Arthroscopic capsular release for contracture of the wrist: a new technique

SUMMARY

Stiffness of the wrist can occur following trauma or surgery. In some patients, loss of motion may be refractory to conservative treatment and operative treatment may thus be indicated. The authors report the results and technique of arthroscopic capsular release of the wrist. A cadaveric study was performed to assess the safety of arthroscopic capsular release. Arthroscopic capsular release was performed on 2 patients with limited wrist mobility. The average distance from the radiocarpal joint capsule to the neurovascular structures were 6.9 mm to the median nerve, 6.7 mm to the ulnar nerve and 5.2 mm to the radial artery. At 6 months follow-up, the average range of motion had improved from 17 degrees flexion and 10 degrees extension to 47 degrees flexion and 50 degrees extension. The average grip strength had improved from 13 to 31 kg. Pain measured on a visual analogue score (0-10) had improved from 1.5 to 1.0. There were no complications. Arthroscopic capsular release of the wrist is a safe and minimally invasive technique that provides good improvement to range of motion.

Uncommon causes of anterior knee pain: a case report of infrapatellar contracture syndrome

The uncommon causes of anterior knee pain should always be considered in the differential diagnosis of a painful knee when treatment of common origins become ineffective. A case is presented in which the revised diagnosis of infrapatellar contracture syndrome was made after noting delayed progress in the rehabilitation of an active female patient with a presumed anterior horn medial meniscus tear and a contracted patellar tendon. The patient improved after the treatment program was augmented with closed manipulation under arthroscopy and infrapatellar injection of both corticosteroids and a local anesthetic. Infrapatellar contraction syndrome and other uncommon sources of anterior knee pain, including arthrofibrosis, Hoffa's syndrome, tibial collateral ligament bursitis, saphenous nerve palsy, isolated ganglions of the anterior cruciate ligament, slipped capital femoral epiphysis, and knee tumors, are subsequently discussed. Delayed functional advancement in a rehabilitation program requires full reassessment of the patient's diagnosis and treatment plan. Alternative diagnoses of knee pain are not always of common origins. Ample knowledge of uncommon causes of anterior knee pain is necessary to form a full differential diagnosis in patients with challenging presentations.

Patellar tendon and infrapatellar fat pad healing after harvest of an ACL graft

Clinical studies have documented proliferation of the host patellar tendon and fibrosis extending into adjacent tissues after reconstruction of the injured anterior cruciate ligament (ACL) using the central one-third of the patellar tendon (PT) as the graft. Such generalized arthrofibrosis has been implicated in knee locking and as possible source of anterior knee pain. However, it is not clinically feasible to measure changes in tendon morphology and mechanical properties and degeneration of peripheral tissues over time following graft harvest. In a rabbit experimental model proliferative changes in the tendon and the infrapatellar fat pad have been documented following harvest of a central third tendon graft without ACL reconstruction. Studies in larger animals have shown significant reductions in the strength and stiffness of the healing patellar tendon, but without assessment of the peripheral tissue response. In the current study an ACL reconstruction was performed in a goat model using an autogenous patellar tendon graft. Extensive tendon and fat pad proliferation were observed along with significant reductions in the biomechanical properties of the host tendon. Significant fat pad fibrosis was documented using biochemical methods. The current data confirm that harvest of an autogenous PT graft for reconstruction of the ACL results in significant changes in the PT and adjacent tissues. These data may help explain some of the clinical complications documented in the reconstructed joint.

Effects of patellar tendon adhesion to the anterior tibia on knee mechanics

The effects of patellar tendon adhesion on the knee extensor mechanism and on the kinematics and contact areas for both the patellofemoral and tibiofemoral joints were determined for five cadaveric knees in an open kinetic chain testing configuration. Patellar tendon adhesion decreased the distance from the inferior patellar pole to the tibial tuberosity, effectively creating patella infera. When compared with the controls, knees with adhesion had medial and distal translation of the patella, as well as increased patellar flexion. Although the patellar articular contact location shifted distally, the overall contact area did not change significantly. For the tibia, adhesion resulted in significant medial, proximal, and anterior translation, and internal rotation. Adhesion also resulted in a posterior shift of the tibial contact location. For the extensor mechanism, adhesion decreased the knee extension force created by the quadriceps muscle on the tibia, indicating a decrease in the effective moment arm of the extensor mechanism. Furthermore, as a result of patellar tendon adhesion, the angle formed by the quadriceps and patellar tendons decreased, suggesting an increase in patellofemoral joint reaction force with adhesion. The increased patellofemoral joint reaction force and the altered contact location may be related to anterior knee pain after knee trauma and knee surgery. Therefore, patients should be observed for subtle patella infera, which may indicate patellar tendon adhesion.

Quantitative analysis of synovial fibrosis in the infrapatellar fat pad before and after anterior cruciate ligament reconstruction

We performed quantitative analysis of synovial fibrosis in the infrapatellar fat pad in 26 patients who underwent arthroscopically assisted anterior cruciate ligament reconstructions. Twelve patients underwent reconstruction with patellar tendon autografts, and 14 had reconstructions with semitendinosus and gracilis tendon autografts. Synovial samples were obtained at the time of reconstruction from 10 patients and at second-look arthroscopy from all 26 patients. Sections from quick-frozen samples were stained with either hematoxylin and eosin or Fast green and Sirius red. We used sodium hydroxide in absolute methanol to elute the Fast green and Sirius red stains, and the total collagen content of each section was estimated by measuring the optical density of the eluted solution. The volume of each section was determined on a computer using an imaging program, and collagen content per unit of tissue was calculated. Median collagen content was 15.3 micrograms/mm3 for the preoperative samples, 25.1 micrograms/mm3 for the group with patellar tendon autografts, and 27.1 micrograms/mm3 for the group with hamstring tendons autografts. Analysis of preoperative and postoperative paired samples revealed a significant increase in synovial collagen after anterior cruciate ligament reconstruction. We observed increased fibrosis in patients who had pain on exertion or stiffness in squatting after the reconstructive surgery.

Classification and management of arthrofibrosis of the knee after anterior cruciate ligament reconstruction

We report 72 patients with disabling knee arthrofibrosis who were treated at our clinic. All patients had painful restriction of extension or limitation of both extension and flexion that had persisted despite physical therapy. The level of arthrofibrosis was categorized into one of four types: Type 1 (25 patients), < 10 degree extension loss and normal flexion; Type 2 (16 patients), > 10 degree extension loss and normal flexion; Type 3 (15 patients), > 10 degree extension loss and > 25 degree flexion loss with a tight patella; and Type 4 (16 patients), > 10 degree extension loss, 30 degrees or more flexion loss, and patella infera with marked patellar tightness. All patients were treated with outpatient arthroscopic surgery. Anterior scar resection down to the proximal tibia was required for all patients with Types 2, 3, and 4 arthrofibrosis. Notchplasty was performed when necessary. Medial and lateral capsular releases and knee manipulation were required for patients with Type 3 or 4 arthrofibrosis. Postoperatively, all patients with Types 2, 3, and 4 arthrofibrosis were treated with outpatient serial extension casting. At the time of latest followup (28 to 115 months), the mean improvement of range of motion was as follows: Type 1, 7 degrees of extension; Type 2, 14 degrees of extension; Type 3, 13 degrees of extension and 28 degrees of flexion; and Type 4, 18 degrees of extension and 27 degrees of flexion. Improvement was also found for the mean stiffness, self-evaluation, functional activity, and Noyes knee scores in all groups.

Patellar height ratios. A comparison of four measurement methods

Three blinded observers on three separate occasions calculated four commonly employed patellar height ratios on the knees of 15 patients who had three lateral radiographs each. The observers used the same measurement instrument, a hand-held goniometer ruler, to determine the relative reliability of each patellar height ratio. The measurements by the three observers were examined, and the error and reliability of the four methods of measurement were tested statistically. Among the four methods of measuring patellar height that we studied, the Blackburne-Peel method most consistently reproduced the patellar height index. Interobserver measurement error averaged 0.06 for all ratios. Values greater than 0.06 represented real patellar height changes. The ratios were not significantly affected by the change of knee flexion angle from 30 degrees to 50 degrees. Side-to-side patellar height measurement differences averaged 0.16, which suggests that the healthy contralateral limb is not reliable as a control. Mild arthritic changes decreased variability of measurements by an average of 24% because small osteophytes better defined the articular margins of the patella.

Prevention of arthrofibrosis after anterior cruciate ligament reconstruction using the central third patellar tendon autograft

A retrospective analysis was performed to explain the decreasing incidence of postoperative arthrofibrosis of the knee in 191 consecutive patients who had anterior cruciate ligament reconstruction using the central third patellar tendon from 1987 through 1991. Follow-up data were available on 188 patients (98%). Age, sex, time interval from injury, preoperative motion, and concomitant meniscal repair or partial meniscectomy were evaluated for their significance as risk factors. Twenty-two of 188 patients (12%) developed arthrofibrosis; the incidence was lower when the acute anterior cruciate ligament reconstruction was delayed at least 3 weeks from the injury, and when preoperative extension was 10 degrees or better. Age, sex, preoperative flexion, and need for concomitant meniscal surgery were not risk factors. The postoperative motion protocol evolved during the study period. Group 1 patients were braced in 45 degrees of flexion for 1 week before passive extension was allowed. In Group 2, motion was started after 48 hours. Group 3 patients were braced in full extension, with motion starting with 24 hours. With these changes, the incidence dropped from 23% to 3%. Decreases in the incidence of arthrofibrosis with modifications in operative technique and postoperative analgesia were not statistically significant.

Arthroscopic management of postoperative arthrofibrosis of the knee joint: indication, technique, and results

From October 1987 through March 1991, 58 patients with postoperative joint stiffness underwent arthroscopic fibroarthrolysis. Forty-six knees in 46 patients were followed. The indication for arthroscopic management was decreased range of motion after surgery. Eighty-seven percent had been treated by arthrotomy. Thirteen percent had been managed by arthroscopic surgery. The indication for primary surgery was a torn anterior cruciate ligament in 74%. The mean interval between arthroscopic fibroarthrolysis and follow-up was 22.1 months. The average age was 32.7 years. A modified Blauth and Jäger score was used for classification of fibroarthrosis: grade I (mild 17.4%), grade II (moderate 63%), grade III (severe 15.2%), and grade IV (bad 4.3%). The gain in range of motion was evaluated by the Cauchoix index: the results were excellent in 54.5%, good in 21.7%, and fair and poor in 23.8%. Pain was evaluated according to a modification of the Lysholm score: 80.4% of the patients experienced a reduction in pain. The sports activity level in the Tegner activity scale increased from 2.3 to 4.8. Patient satisfaction was excellent or good in 56.5% (n = 26), fair in 39.1% (n = 18), and poor in 4.3% (n = 2). On the basis of our retrospective study, we feel that arthroscopic fibroarthrolysis is of benefit to the patients with postoperative joint stiffness even after a prolonged period.

Stiffness of the knee--mixed arthroscopic and subcutaneous technique: results of 67 cases

This study is an analysis of the treatment for mixed-cause stiffness of the knee: intraarticular and extraarticular. We examined 67 patients. The cause of stiffness was mostly ligamentous surgery, found in 51 cases (76%). Preoperative range of motion was 11 degrees extension and 89 degrees flexion. In 14 cases extension was complete. In the remaining 53 cases, extension was limited. Results achieved with arthroscopic arthrolysis were generally excellent. The ideal time to perform the operation is within the first 9 months after injury. The best results were obtained in the 7th month. Results deteriorate notably after 1 year. The age of the patient does not seem to affect the end result.

Arthroscopic lysis in knee arthrofibrosis

Arthrofibrosis continues to be a difficult complication in articular surgery on the knee. We present our experience in 21 cases of arthroscopic lysis as an alternative to mobilization under anesthesia. The technique begins with the liberation of the adhesions of the suprapatellar pouch, continues down both gutters, and ends with a cleaning of the notch where necessary. When a restriction of patellar mobility persists, we make a retinacular release. The results obtained are very satisfactory, with an average increase in the arc of mobility of 68 degrees. The average gain in mobility at 6 months is significantly greater than that achieved in the immediate postoperative period. Longer follow-up showed no improvement in range of motion after 6 months.