Editorial Commentary: To Treat or Not to Treat? Are We Any Closer to Knowing What to Do With Cartilage Lesions of the Tibia?

The increasing interest and use of cartilage repair procedures in the knee has led to a better understanding of when and how chondral lesions should be treated. Nonetheless, there are still key areas where we lack understanding and need better data to guide clinical decision making. One of these areas is how to manage lesions of the tibia, particularly when they occur in conjunction with the more commonplace lesions of the femoral condyle. In this setting, a tibial chondral lesion may reflect a bigger clinical problem—a “bipolar defect” or more advanced joint disease—“established osteoarthritis.” My preferred treatment for these tibial lesions is to ignore the lesion (or perform a chondroplasty at most), except in cases of osteochondritis dissecans, focal defects in association with cysts, or tibial plateau fracture malunion.     

自体软骨膜、骨膜游离移植修复软骨缺损治疗骨性关节炎

目的：评价自体软骨膜或骨膜游离移植术修复膝关节大面积软骨缺损，治疗膝关节骨性关节炎的疗效。方法：将髌骨及股骨髁，胫骨平台病损软骨清除，游离移植软骨或骨膜修复软骨缺损，治疗骨性关节炎124例，术后不需外固定，4天后持续被动关节活动器作持续动活动。2周后下床活动，结果：术后平均随访6年，治疗效果满意。结论：采用自体软骨膜，骨膜游离移植修复大面积软骨缺损，治疗骨性关节炎，可取得满意效果。     

Analysis of articular cartilage lesions in 5114 knee arthroscopies]

The cartilage lesions become the increasing social problem, which occurs often in young people. It influences the normal knee function and may predispose patients for osteoarthritis. The aim of this study was the epidemiologic and etiological analysis of the knee articular cartilage lesions diagnosed in arthroscopy. From 1997 to 2002, arthroscopy of the knee joint was performed in 5114 patients. Chondral lesions were found in 2931 cases--57.3. Non-isolated cartilage lesions accounted for 67.9%. Grade II according to ICRS classification evaluated in arthroscopy was the most frequent grade of the cartilage lesion (47.8%) and grade 4B the least frequent one (0.11%). The patellar articular surface (43.3%) and the medial femoral condyle (39.6%) were the most common locations of the lesions.     

Localization of the full‐thickness cartilage lesions in medial and lateral unicompartmental knee osteoarthritis

This study's aim was to determine the patterns of osteoarthritis (OA) in both unicompartmental medial and lateral OA of the knee. Forty patients with medial and 20 with lateral unicompartmental knee osteoarthritis were studied to determine the location of full‐thickness cartilage lesions. Intraoperatively, the distance between margins of the lesion and reference lines were measured. The femoral measurements were transposed onto lateral radiographs to determine the relationship between the lesion site and knee flexion angles. Both tibial and femoral lesions were significantly (p < 0.01) more posterior in lateral OA than medial OA. In medial OA, the lesion center was, on average, at 11° (SD 3°) of flexion, whereas in lateral OA, it was at 40° (SD 3°). The smallest medial femoral lesions were near full extension and, as they enlarged, they extended posteriorly. The smallest lateral femoral lesions extended from 20° to 60° flexion. As these lesions enlarged, they extended both anteriorly and posteriorly. There was a well‐defined relationship between the site of the lesions and their size, suggesting that they develop and progress in a predictable manner. The relationship was different for medial and lateral OA, suggesting that different mechanical factors are important in initiating the different types of OA. The lesions in medial OA occur in extension, perhaps initiated by events occurring at heel strike. The lesions in lateral OA begin at flexion angles above those occurring during the single leg stance phase of the gait cycle, so activities other than gait are likely to induce lateral OA. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1339–1346, 2009     

Osteochondral autografts transfer for post-traumatic osteochondral defect of the knee-2 to 5 years follow-up

The treatment of post-traumatic osteochondral defects of the weight-bearing surface of the knee in young active patients remains a significant challenge. We report the results of an osteochondral autograft transfer (OAT) in 18 patients (mean age 29 years) with post-traumatic focal osteochondral defects of the knee. Sixteen lesions were over the femoral condyle and two were over the tibial plateau. The average size of the lesion was 4.1 cm² (from 2.25 to 6 cm²), and the subchondral bone involved no more than 1 cm in depth. Osteochondral grafts were harvested from the non-weight-bearing area of the femoral condyle. Ten patients also had concomitant surgical procedures. The average follow-up was 42 months (from 24 to 64 months). All patients were evaluated by Lysholm and Tegner activity scores and plain radiographs. Nine patients had MRI, eight patients had second-look arthroscopy and two had a biopsy. Sixteen patients (89%) had good to excellent results, while two patients with lesion over the tibial surface had fair results. The biopsy revealed survival of hyaline cartilage. For small to medium osteochondral lesion over the femoral condyle of the knee in selected patients, osteochondral autografting yielded promising short to mid-term results.     

Effect of high tibial flexion osteotomy on cartilage pressure and joint kinematics: a biomechanical study in human cadaveric knees

Introduction Valgus high tibial osteotomy is an established treatment for unicompartmental varus osteoarthritis. However, only little is known about the effect of osteotomy in the sagittal plane on biomechanical parameters such as cartilage pressure and joint kinematics. This study investigated the effects of high tibial flexion osteotomy in a human cadaver model.Materials and methods Seven fresh human cadaveric knees underwent an opening wedge osteotomy of the proximal tibia in the sagittal plane. The osteotomy was opened anteriorly, and the tibial slope of the specimen was increased gradually. An isokinetic flexion-extension motion was simulated in a kinematic knee simulator. The contact pressure and topographic pressure distribution in the medial joint space was recorded using an electronic pressure-sensitive film. Simultaneously the motion of the tibial plateau was analyzed three-dimensionally by an ultrasonic tracking system. The traction force to the quadriceps tendon which was applied by the simulator for extension of the joint was continuously measured. The experiments were carried out with intact ligaments and then after successively cutting the posterior and anterior cruciate ligaments.Results The results demonstrate that tibial flexion osteotomy leads to a significant alteration in pressure distribution on the tibial plateau. The tibiofemoral contact area and contact pressure was shifted anteriorly, which led to decompression of the posterior half of the plateau. Moreover, the increase in the slope resulted in a significant anterior and superior translation of the tibial plateau with respect to the femoral condyles. Posterior subluxation of the tibial head after cutting the posterior cruciate ligament was completely neutralized by the osteotomy. The increase in slope resulted in a significant higher quadriceps strength which was necessary for full knee extension.Conclusions We conclude from these results that changes in tibial slope have a strong effect on cartilage pressure and kinematics of the knee. Therapeutically a flexion osteotomy may be used for decompression of the degenerated cartilage in the posterior part of the plateau, for example, after arthroscopic partial posterior meniscectomy. If a valgus osteotomy is combined with a flexion component of the proximal tibia, complex knee pathologies consisting of posteromedial cartilage damage and posterior and posterolateral instability can be addressed in one procedure, which facilitates a quicker rehabilitation of these patients.Winner of the AGA-DonJoy Award 2003     

Tensile properties of articular cartilage are altered by meniscectomy in a canine model of osteoarthritis.

Loss of or damage to the meniscus alters the pattern of loading in the knee joint and frequently leads to cartilage degeneration and osteoarthritis. The mechanical properties of articular cartilage have been shown to reflect the extent of cartilage degeneration in human osteoarthritis and in experimental models of joint disease, but there is little experimental data documenting changes in cartilage mechanics following meniscectomy. We hypothesized that the tensile properties of the surface zone of articular cartilage are altered following total medial meniscectomy. Twelve mongrel dogs underwent complete resection of the medial meniscus in the right knee, and the femoral cartilage was studied 12 weeks after the operation. We performed uniaxial, tensile stress-relaxation tests to determine the equilibrium tensile modulus of surface-zone cartilage. Water and glycosaminoglycan content were also measured at site-matched locations. The tensile moduli of the cartilage decreased significantly following meniscectomy. The linear region modulus decreased by 40%, from 25.5 +/- 7.7 to 15.3 +/- 7.2 MPa. There was a weak (r = -0.45), but significant, correlation between the linear region modulus and the gross morphological grade for cartilage damage. Water and glycosaminoglycan content did not change following meniscectomy. Composition was not correlated with mechanical properties or morphological grade, suggesting that cartilage structure may play a more important role than composition in determining the mechanical properties. The observed decrease in cartilage material properties provides a quantitative measure of the loss of cartilage function following meniscectomy and reflects a pattern of change that is consistent with damage to the collagen-proteoglycan solid network.     

Juxta-articular bone marrow signal changes on magnetic resonance imaging following arthroscopic meniscectomy

Purpose: Postmeniscectomy osteonecrosis of the knee has been reported in the past decade but the etiology remains unclear. Some investigators have indicated that bone marrow signal changes evident on magnetic resonance imaging (MRI) could be early warning signs of osteonecrosis. The purpose of this study was to determine the incidence rate, location, and magnitude of such changes in bone marrow of the knee after arthroscopic meniscectomy, using MRI. Type of Study: Cohort analytic study. Methods: Ninety-three patients with no bone marrow signal abnormalities on preoperative MRI were examined after isolated arthroscopic meniscectomy. There were 51 men and 42 women with an age range of 11 to 62 years (mean, 36.6 years). Of the total, 57 patients underwent partial meniscectomy (34 medial and 23 lateral) and the others total meniscectomy (10 medial and 26 lateral). MRI examinations were performed independently of postoperative knee symptoms, 1 to 24 months after surgery. Bone marrow changes of the treated knees were evaluated by T1- and T2*-weighted MRI. Results: Thirty-two of 93 patients (34%) had bone marrow signal changes in femoral or tibial condyles shown on postoperative MRI. No patients had these changes in the femoral or tibial condyles opposite from the meniscectomy side and, in the majority of cases, the size was less than half that of the condyle. Fifteen of the 44 patients who underwent medial meniscectomy and 17 of the 49 patients who underwent lateral meniscectomy had such changes. The meniscectomy side did not affect the incidence rate, and frequently both femoral and tibial condyles were involved. Age, gender and articular cartilage condition at the surgery were not risk factors. In contrast, the extent of meniscectomy affected the incidence rate. Conclusions: This study suggests a positive correlation between arthroscopic meniscectomy and postoperative bone marrow signal changes of the knee.Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol 18, No 3 (March), 2002: pp 238–245     

Early osteoarthritis in young sportsmen with severe anterolateral instability of the knee

In a retrospective study of patients presenting with symptoms of knee instability, 16 patients were discovered who had developed severe chondromalacia or osteoarthritis of the femoral condyles. All of the patients gave a history of a previous severe knee injury occurring in their teenage years and all had continued to play competitive sport. Ten of the group had subsequent meniscal injuries requiring surgery. In nine of the group previous arthroscopic or open joint procedures had demonstrated normal femoral joint cartilage. There was no difference in the degree of degeneration in those who had had a meniscectomy as compared with those who had not had meniscal damage. It is concluded that severe anterolateral instability is a cause of early degenerative joint disease in young athletes even in the absence of meniscal damage and that they should be strongly advised against participating in active sport until the joint has been stabilized.     

Role of arthroscopy in osteoarthritis of the knee.

We compared arthroscopic partial menisectomy with limited debridement versus arthroscopic abrasion arthroplasty in patients with osteoarthritis. Group I consisted of 131 knees in 131 patients treated by partial meniscectomy and debridement of loose articular cartilage or removal of loose bodies. All patients had grade 3 or 4 chondromalacia in the affected compartment. The patients were followed for a mean of 3 +/- 1 years. Group II consisted of 28 knees in 28 patients treated by debridement with abrasion arthroplasty of exposed bone. The mean age of this group of patients was 63 years and they were followed for a mean of 3.8 years. The Group I patients noted 80% improvement by 1 year but this fell to 67% by 5 years after meniscectomy. Overall, 104 were improved, 16 unchanged, and 15 worse at the time of last evaluation compared to their preoperative status. In the Group II patients, 11 were improved, 8 unchanged, and 9 worse. Fifty percent of Group II subsequently underwent a total knee arthroplasty for salvage at a mean of 3 years following the abrasion procedure. Abrasion arthroplasty appears to offer little benefit over partial meniscectomy and debridement in the degenerative knee. Results of abrasion arthroplasty are unpredictable.     

Articular cartilage lesions in the symptomatic anterior cruciate ligament-deficient knee

Purpose: The goal of the study was to report the prevalence of the lesions of the articular cartilage of the femoral condyles and tibial plateau in patients with a symptomatic anterior cruciate ligament (ACL)-deficient knee undergoing day-case arthroscopy. Type of Study: Case series study. Methods: We studied 378 skeletally mature patients (average age, 27.3 years; range, 16–50 years; 282 men and 84 women), part of a sample of 1,978 patients undergoing a primary knee arthroscopy between January 1986 and August 1993. The articular cartilage lesions were classified according to Outerbridge by a single observer. We assessed the relationship between time of injury and articular cartilage lesions and between meniscal lesions and articular cartilage lesions. Results: A complete ACL tear was found in all 378 knees. Of these, 157 showed at least one lesion of the articular cartilage. The medial femoral condyle (MFC) showed the highest frequency of articular cartilage lesions, especially in the weight-bearing portion. Patients with a bucket-handle tear of the medial meniscus had greater degeneration of the MFC than those with other meniscal tears. A meniscal tear was associated with a greater degree of articular damage. The second most common lesion was a combined lesion of the medial and lateral compartments, followed by isolated lateral compartment lesion. A time-dependent pattern of development of articular cartilage lesions was identified. Conclusions: In patients with more advanced degenerative changes, the time from injury to arthroscopy was significantly longer than in patients with lesser articular surface abnormalities, and the presence of a meniscal tear was associated with a greater degree of articular cartilage damage. Patients with a symptomatic ACL-deficient knee and an associated tear of the medial meniscus are at high risk of having a lesion of the articular surface of the weight bearing area of the knee.     

The long-term effects of hyaluronan during development of osteoarthritis following partial meniscectomy in a rabbit model

OBJECTIVE: The long-term effect of hyaluronan (HA) on meniscus remodeling and articular cartilage preservation was assessed during the development of osteoarthritis following partial meniscectomy in a rabbit model. DESIGN: Approximately 60% of the region of each medial meniscus of 20 rabbit knees was excised bilaterally. The left knee joint was treated with five weekly intraarticular injections of 0.3 ml of HA, beginning 1 week after surgery. The right control knee was injected with PBS on the same schedule. Six months after surgery, animals were killed and the medial menisci and tibial articular cartilage were evaluated morphologically, histologically and biochemically. RESULTS: Meniscal regeneration was observed as newly synthesized translucent tissue, and image analysis revealed that the amount of this tissue was significantly greater in the HA-treated menisci than in the vehicle-treated menisci. Safranin-O staining and image analysis revealed the increased presence of glycosaminoglycans in the HA-treated menisci relative to vehicle-treated menisci while vascularity and biochemical parameters (hydration, total GAGs and reducible collagen crosslinks) were statistically similar in HA- and vehicle-treated menisci. Gross morphologic grading with India ink revealed a trend for less deterioration of tibial articular cartilage in the HA group (P=0.09) while Mankin's score of the HA-treated tibial articular cartilage was marginally lower than that of the vehicle group (P=0.06). Biochemical assessments showed a trend for higher total GAGs concentration in the HA-treated articular cartilage when compared to the vehicle treatment group (P=0.06). CONCLUSION: The present study has demonstrated that following partial meniscectomy, treatment with hyaluronan can enhance meniscal regeneration and may inhibit articular cartilage degeneration as long as six months post surgery.     

Articular cartilage MR imaging and thickness mapping of a loaded knee joint before and after meniscectomy

OBJECTIVE: We describe a technique to axially compress a sheep knee joint in an MRI scanner and measure articular cartilage deformation. As an initial application, tibial articular cartilage deformation patterns after 2 h of static loading before and after medial meniscectomy are compared. METHODS: Precision was established for repeated scans and repeated segmentations. Accuracy was established by comparing to micro-CT measurements. Four sheep knees were then imaged unloaded, and while statically loaded for 2 h at 1.5 times body weight before and after medial meniscectomy. Images were obtained using a 3D gradient echo sequence in a 4.7 T MRI. Corresponding 3D cartilage thickness models were created. Nominal strain patterns for the intact and meniscectomized conditions were compared. RESULTS: Coefficients of variation were all 2% or less. Root mean squared errors of MR cartilage thickness measurements averaged less than 0.09 mm. Meniscectomy resulted in a 60% decrease in the contact area (P=0.001) and a 13% increase in maximum cartilage deformation (P=0.01). Following meniscectomy, there were greater areas of articular cartilage experiencing abnormally high and low nominal strains. Areas of moderate nominal strain were reduced. CONCLUSIONS: Medial meniscectomy resulted in increased medial tibial cartilage nominal strains centrally and decreased strains peripherally. Areas of abnormally high nominal strain following meniscectomy correlated with areas that are known to develop fibrillation and softening 16 weeks after medial meniscectomy. Areas of abnormally low nominal strain correlated with areas of osteophyte formation. Studies of articular cartilage deformation may prove useful in elucidating the mechanical etiology of osteoarthritis.     

Nucleic Acids in Human Normal and Osteoarthritic Articular Cartilage

During operations on joints of patients with osteoarthritis, specimens of severely degenerated cartilage of the femoral head were removed and cartilage from knee joints taken at meniscectomy was used as control material. DNA and RNA concentrations were reduced in advanced osteoarthritis, while the synthesis of DNA and RNA was increased in relation to the number of cells in the tissue. The result showed that in advanced osteoarthritis the remaining chondrocytes are metabolically very active.     

How to Manage Cartilage Injuries?

Although small cartilage injuries are commonly found in knee arthroscopy procedures, significant chondral and osteochondral injuries are relatively infrequent. Incidence of cartilage injury rises when considering traumatic origin, especially when approaching significant ligamentous or meniscal pathology. Options for restoration span the gamut from benign neglect to open procedures that restore both cartilage and subchondral bone. The best choice of procedure largely depends on lesion size, depth, and location. Smaller lesions isolated to cartilage <2 cm² can be treated with marrow stimulation techniques such as microfracture with or without biologic options (bone marrow aspirate concentrate or platelet-rich plasma with or without cartilage precursors or scaffolds). Microfracture alone in larger lesions has been reported to be less durable and it is therefore not recommended for larger lesions. Smaller lesions <2 cm² that include a subchondral injury can be treated with osteochondral autograft implantation, in which a core of cartilage and bone is transferred from a relative non-weightbearing surface to the lesion.Larger osteochondral lesions >2 cm² are better treated with osteochondral allograft transplantation, where osteochondral cores from a size-matched, fresh cadaver are matched to the patient's lesion. This option may require multiple cores to be placed in a “snowman” pattern; however, recent literature demonstrated that a single plug might produce better outcomes. Alternatively, for large chondral-only lesions, a resurfacing procedure may be chosen that may include biologic options. Autologous chondrocyte implantation (ACI), currently in its third iteration (matrix ACI [MACI]), is an excellent choice with good long-term durability. In addition, MACI may be used for chondral lesions in the patellofemoral joint where matching the native joint topology may be more difficult. If the patient has an underlying bone marrow lesion but an intact cartilage cap that appears healthy on arthroscopic examination, one may consider a core decompression and injection with biologics such as BMAC and bony scaffold with fibrin glue (also known as bioplasty).It is also critical that the surgeon address any concomitant knee pathology that would compromise cartilage restoration. This includes addressing malalignment with distal femoral, proximal tibial, or tibial tubercle osteotomy, significant meniscal deficiency with meniscal transplant, and any instability from lack of cruciate or collateral ligaments with ligament reconstruction.     

Degenerative lesions in the articular cartilage after meniscectomy: preliminary experimental study in dogs

Articular cartilage degeneration was studied in an experimental model including 68 knees of adult dogs on which five different types of medial meniscectomy had been performed with a followup period of 10 to 450 days. The results were assessed by macroscopic, radiologic, and histologic methods. The degenerative lesions increased proportionally to the amount of meniscal tissue resected and the duration of observation. These lesions proved to be more intense at the tibial plateau compared to the femoral condyle. For both joint surfaces the predominant location was the central zone. Considering the degenerative process by the articular cartilage after total meniscectomy, maximum preservation of meniscal tissue is recommended.     

Subchondral giant-cell tumor of the proximal tibia: arthroscopic treatment for accelerated articular cartilage and meniscal degeneration in two patients

Giant-cell tumor most commonly occurs in the distal femur and proximal tibia and characteristically involves the subchondral bone. Incomplete resection leads to recurrence rates of up to 50%. Intralesional curettage, adjuvant treatments, and polymethyl methacralate (PMMA) reconstruction is the current mainstay of treatment and has produced recurrence rates of less than 10%. Achieving adequate curettage while preserving the articular cartilage of the tibial plateau poses a significant challenge, especially when the tumor involves the subchondral bone. We report on 2 cases, both with symptomatic full-thickness tibial articular cartilage loss and one with a meniscal tear, after curettage, phenol cautery, and PMMA reconstruction of giant-cell tumor of the proximal tibia. Arthroscopic chondroplasty and planing of the exposed cement was performed in both cases, theoretically reducing focal areas of stress concentration that could lead to further meniscal damage and injury to the femoral condyle articular surface in weight-bearing. Partial meniscectomy for a complex meniscal tear was performed in one case. Eighteen months postoperatively, both patients were asymptomatic, working full-time, and participating in light physical activity. Repetitive heavy loading of the knee, such as running, was prohibited, and long-term follow-up is warranted to assess for further joint degeneration and need for total knee arthroplasty.     

Articular cartilage lesions of the knee

The pathogenesis and clinical significance of articular cartilage lesions of the knee persist as topics of considerable interest among orthopedic surgeons. This study was designed to assess the association of articular cartilage degeneration with concomitant intraarticular abnormalities and to correlate the prevalence and severity of articular cartilage damage with preoperative historical and physical exam findings in patients presenting with knee pain. Twenty-six history and physical exam data points were prospectively collected from 192 patients (200 knees), consecutively undergoing arthroscopic knee surgery. During surgery, all articular cartilage lesions were recorded with respect to size, location, and character and were graded according to Oglivie-Harris et al. All concomitant knee joint abnormalities were simultaneously recorded. Of 200 knees examined arthroscopically, 12 knees revealed no demonstrable etiology for the presenting symptoms, 65 knees revealed assorted intraarticular pathology but no articular cartilage degeneration, and the remaining 123 knees revealed a total of 211 articular cartilage lesions (103 femoral, 72 patellar, 36 tibial); 7 femoral, 6 patellar and 0 tibial lesions were completely isolated (no concomitant knee joint pathology). The concomitance of femoral defects with tibial lesions was highly significant (p = 0.01). Femoral and tibial articular cartilage lesions were strikingly correlated with the presence of an unstable torn meniscus (p less than 0.001). Medial compartment articular cartilage lesions were significantly more common (p = 0.001), more closely associated with meniscal derangement, and appreciably more severe than lateral compartment lesions. In 75% of anterior cruciate ligament-deficient knees with concomitant articular cartilage degeneration, the duration from injury to surgery was greater than 9 months, and in each of these cases, a history of reinjury to the knee was elicited. From these data one can conclude that: (a) in some patients with painful knees, isolated articular cartilage lesions may be the only abnormality noted at arthroscopy; (b) unstable meniscal tears are significantly associated with destruction of articular cartilage; (c) the medial compartment is particularly susceptible to articular cartilage degeneration; and (d) in our series, anterior cruciate ligament tears were increasingly associated with articular cartilage destruction as the elapsed time from injury to arthroscopy increased.     

Upper tibial osteotomy for secondary osteoarthritis of the knee

Of 34 consecutive proximal tibial osteotomies for secondary degenerative arthritis in patients under 40 years of age, 33 were evaluated at least three years (mean 7.5 years) after operation. In all 73% were satisfactory, with four failures in 21 procedures in men and five failures in 12 procedures in women. The primary abnormalities were medial meniscectomy (11), medial and lateral meniscectomy (4), osteochondritis dissecans (3), osteochondritis dissecans with medial meniscectomy (4) and fracture (11). All four knees with both medial and lateral meniscectomy had unsatisfactory results despite obtaining anatomical alignment. Eight patients needed subsequent surgery; five of them had total knee replacement, four within four years of the osteotomy. Proximal tibial osteotomy in younger patients with secondary arthritis gives similar results to those for older patients with primary osteoarthritis. If it fails, this is generally within the first four years after the operation.