Pole Of Patella Research Articles

Evaluation of the isometry of different points of the patella and femur for medial patellofemoral ligament reconstruction

BackgroundThe location of patellar and femoral fixation of the graft in medial patellofemoral ligament reconstructions has been widely discussed. This study aimed to assess the distances between different patellar and femoral fixation points to identify the least anisometric pairs of points. MethodsTen cadaver knees were attached to an apparatus that simulated an active range of motion of 120°, with three metallic markers fixed onto the medial side of the patella, and seven markings onto the medial epicondyle. The examined points included the proximal patella pole (1), the patellar center (3), the midpoint between points 1 and 3 (2), a point directly on the epicondyle (6), points 5mm anterior (5) and posterior (7) to the epicondyle, points 5mm anterior to point 5 (4) and 5mm posterior to point 7 (8), and points 5mm proximal (9) and distal (10) to the epicondyle. The distances between patella and femur points were measured by a photogrammetry system at 15° intervals. FindingsThe pair of points that exhibited the lowest average variability in distance, and hence was the most isometric, was the patella center combined with the anterior to the medial femoral epicondyle. The pairs of points that exhibited the highest average variability in distance, and hence were the least isometric, were the ones located distal or posterior to the medial femoral epicondyle, with less influence by the patellar location. InterpretationSurgeons should avoid positioning the graft distally or posterior to the epicondyle due to the increase in anisometry.

Surgical Treatment of Neglected Traumatic Quadriceps Tendon Rupture with Knee Ankylosis.

Quadriceps tendon rupture is an uncommon injury. This disabling condition is the result of direct or indirect trauma. It requires surgical repair to avoid poor outcomes in cases of neglected or chronic rupture. In most acute cases, simple tendon suture or reinsertion is suitable for an extensor mechanism reconstruction of the knee joint. However, chronic lesions often require a tendon graft or flap reconstruction. We report a case of a 15-year-old male who was diagnosed with a chronic quadriceps rupture with a patellar superior pole fracture. We performed quadriceps reconstruction using tibialis anterior allograft tendon and additional screw fixation to reconstruct the extensor mechanism and recover knee joint range of motion to prevent a high-level functional restriction. The treatment was difficult and limited due to neglect for 9-months that led to ankylosis accompanied with nonunion of tibial fracture. Our surgical treatment using allograft tendon resulted in a very good outcome after 30 months of follow-up.

Area of Skin Numbness After Total Knee Arthroplasty: Does Minimally Invasive Approach Make Any Difference From Standard Approach?

BackgroundSkin numbness after total knee arthroplasty (TKA) was reported in relation to injury of the infrapatellar branch of saphenous nerve (IPBSN). MethodsPhase I study: A nonrandomized and nonconsecutive selection of 30 patients undergoing unilateral TKA, using minimally invasive surgery approach, and 30 patients having standard approach were included. Area of skin numbness was periodically evaluated and compared until 1-year follow-up (FU). Phase II study: we dissected 15 normal cadaveric knees and followed the course and distribution of IPBSN. ResultsTwenty-nine predominantly female patients in each group completed 1-year FU with no differences in demographic data. Both the groups had significantly improved Knee Society Score clinical and function scores with no statistical differences. The numb areas in both the groups similarly decreased from 2 weeks (51.7 cm2 vs 51.1 cm2) to 1 year (2.1 cm2 vs 2.4 cm2) with similar percentages of no skin numbness at 1 year (69% vs 65%). The IPBSN branched from saphenous nerve before exiting the adductor canal and ran longitudinally and obliquely. It was found as a single nerve in 20%, a 2-branch nerve in 67% and a 3-branch nerve in 13%. All branches crossed the knee midline between superior patellar pole and tibial tubercle. ConclusionClinical study showed that TKA using minimally invasive surgery approach provided similar area of skin numbness to standard approach. Numbness area gradually decreased at serial FUs in both the groups. The cadaveric study demonstrated that the IPBSN consistently gave no branch passing the knee midline above superior patellar pole.

Effect of different postoperative flexion regimes on the outcomes of total knee arthroplasty: randomized controlled trial.

A consistent limb position strategy could be an attractive and easier alternative to reduce blood loss and increase range of motion following total knee arthroplasty. The aim of this study was to understand the proper amount of flexion required to improve functional outcomes with limited patients' discomfort. Eighty-five patients undergoing total knee arthroplasty were randomly assigned to receive mild (30° of knee flexion) or high-flexion protocol (70° of knee flexion), 48h after surgery. The same daily rehabilitation scheme was followed. Total blood loss, hidden blood loss, haemoglobin and haematocrit levels, fixed flexion deformity, range of motion and limb circumference at the superior patellar pole were evaluated preoperatively and 7days after surgery. Demographics, blood parameters and preoperative range of motion did not show any significant difference between the two groups. No complications were recorded in both groups. High-flexion group had greater rate of dropout due to excessive patients' discomfort. A significantly lower Hb at day 1 was found in the high-flexion group. No differences were recorded regarding the remaining parameters. No significant differences were found between the high-flexion and mild-flexion protocols; however, mild-flexion protocol was better tolerated by patients. We therefore recommend a 30° flexion protocol to be routinely used 48h postoperatively after total knee arthroplasty. This is an easy strategy to improve functional outcomes, which is a fundamental issue considering the steady increase in knee prostheses utilization. Randomized controlled trial, Level II.

A study to evaluate importance of length from tip of olecranon to the tip of little finger in pre-operative assessment of K-nail in fracture shaft of femur in a tertiary care hospital of Bareilly district

Background: The magnitude of incidence of femoral shaft fracture is approximately 15-20 fractures per 1,00,000 person years. Most commonly intramedullary nailing is preferred for adult femoral shaft fracture. The objective of this study was to assess the intra-medullary femoral nail length in adults by various methods in fracture shaft of femur and to access correlation between these lengths. Methods: Study was conducted on 100 adult healthy volunteers including 41 males and 59 females attending the orthopaedic O.P.D of a tertiary medical college in North India. The length from tip of olecranon to the tip of little finger and the length from tip of the greater trochanter to the upper pole of patella of the same side were measured using a measuring tape on a couch. Results: Analysis showed that the mean length from tip of olecranon to the tip of little finger and the length from tip of the greater trochanter to the upper pole of patella of the same side were 42.175 (SD, 2.0641) and 42.093 (SD, 2.0846) respectively. The mean difference between these two measurements was 0.083 (95% CI, 0.020 to 0.145). The significant correlation was found between these 2 lengths i.e. 0.987 by Pearson co-relation (95% CI, 0.977 to 0.994) (p<0.001). Age, sex and body mass index did not affect this correlation. Conclusions: The length from the tip of the olecranon to the tip of the little finger correlated with the femoral length and is more convenient to perform and can also be used when the patient has sustained bilateral fractures of femur.

Repair of comminuted fracture of the lower patellar pole.

Comminuted fracture of the lower patellar pole has characteristics of both patellar fracture and avulsion of the patellar tendon. Therefore, components of both injury types should be considered during treatment. None of the traditional techniques has proven sufficient alone. Currently described is technique that incorporates principles of osteosynthesis as well as repair of the patellar tendon. Total of 23 patients with comminuted fracture of the lower patellar pole were treated surgically and prospectively followed for 24 months. All patients returned to pre-injury level of activities of daily living at average of fourth postoperative month. Average score on scale described by Böstman et al. was 28.1 points. All fractures united within average of 10 weeks. Patellar height was preserved. Only 4 patients, all post-menopausal, demonstrated increase in degenerative changes in patellofemoral joint. Successful osteosynthesis of the comminuted lower patellar pole using the present technique reduces potential need for partial patellectomy, and preserves original length of the extensor mechanism. Present technique allows for immediate full weight-bearing and early, extensive rehabilitation program.

Cannulated screws plus separate vertical wirings for fixation of acute patella inferior pole fracture

Objective To investigate the feasibility and clinical effect of cannulated screws plus separate vertical wirings technique for acute fracture of the inferior pole of the patella. Methods From May 2012 to September 2013, 14 patients with fresh closed unilateral fracture of the inferior pole of the patella were treated with the cannulated screws plus separate vertical wirings. Eight patients were injured in traffic collisions and 6 in fall accidents. Fracture AO classification was type 34A1 in 8 patients and type 34A2 in 6 patients. Time from injury to operation was 1-7 days (mean, 2.5 days). Number of tie wires was determined according to the degree of fracture comminution. Fracture healing, fixed position and patellar length were evaluated by radiographic examination postoperatively. Knee mobility and Bostman evaluation system were investigated to analyze the clinical effect. Results All the patients obtained average 15-month follow-up (range, 12 to 29 months). At postoperative 2 months, the fracture healed with good alignment of the broken bone and proper place of the internal fixation device noted on the X-ray films. At postoperative 6 and 12 months, X-ray films revealed fracture bony healing, good location of the wire internal fixation, and no apparent shortening of the patella. At the 12 months, range of knee motion was (126.0±4.5) ° for flexion and (2.0±1.7) ° for extension. Bostman functional score for patella fracture was (28.1±1.9)points. And 12 patients were rated as excellent and 2 good, with excellence rate of 100%. Conclusion Cannulated screw fixation plus separate vertical wiring is effective to stabilize patella inferior pole fracture and has good results, indicating a recommended surgical method. Key words: Patella; fracture fixation, internal; Cannulated screws

Temperature-controlled continuous cold flow device versus traditional icing regimen following anterior cruciate ligament reconstruction: a prospective randomized comparative trial.

Anterior cruciate ligament (ACL) reconstruction requires an intensive rehabilitation program to be completely successful. Cryotherapy has been described to be helpful in reducing post-operative pain and edema. Aim of this prospective randomized study is to compare two homogeneous groups of patients, one receiving traditional icing regimen and the other a temperature-controlled continuous cold flow device, in post-operative setting after ACL reconstruction. Forty-seven patients treated for ACL reconstruction using "over the top" technique were enrolled for this study. All patients received the same elastocompressive bandage. Regarding the coolant device, 23 patients were randomized to temperature-controlled continuous cold flow device (Hilotherm® group) and 24 patients were randomized to receive ice bag (control group). The two groups were homogenous for pre-operative (age, sex, and time "lesion to surgery") and intra-operative parameters (duration of the procedure, meniscectomy, and chondral damage). NRS (numeric rating scale), blood loss, knee volume increase at three established sites, ROM, and pain killers consumption were assessed. The subjective evaluation of the device including practicality and usefulness of the device was investigated. Hilotherm group resulted in lower pain perception (NRS), blood loss, knee volume increase at the patellar apex and 10 cm proximal to the superior patellar pole, and higher range of motion (p < 0.05) in the first post-operative day. No difference in pain killers consumption was noted. Hilotherm device was considered "comfortable" and "useful" by the majority of patients. Hilotherm group showed significant better results in first post-operative day. Further studies with higher number of patients and longer follow-up are required to assess the beneficial effects on rehabilitation and the cost-effectiveness of the routinely use of this device. II.

Erythropoietin stimulates patellar tendon healing in rats

BackroundErythropoietin (EPO), regulating erythropoiesis, is used to provide protective and regenerative activity in non-haematopoietic tissues. There is insufficient knowledge about the role of EPO activity in tendon healing. Therefore, we investigated the effect of EPO treatment on healing in rat patellar tendons. MethodsOne hundred and twenty-six, four-month-old male Sprague–Dawley rats were randomly assigned to three experimental groups: 1, no treatment; 2, treatment with isotonic saline (NaCl) and 3, treatment with EPO. Each group was randomly subdivided into two groups for sacrifice at three (1a, 2a, 3a) or sixweeks (1b, 2b, 3b). Complete incision of the left patellar tendon from the distal patellar pole was performed. We applied body casts for 20days after the incised edges of the patellar tendon were brought together with a surgical technique. Both legs were harvested and specimens from each group underwent histological, biomechanical, and protein mRNA expression analyses. ResultsThere were statistically significant differences in the ultimate breaking force between the EPO group and others at both weeks three and six (p<0.05); significant differences in fibroblast proliferation, capillary vessel formation, and local inflammation were found between groups 1a and 3a, and 2a and 3a (p<0.05). There were statistical differences between 1a, 3a and 2a, 3a for Col III, TGF-β1, and VEGF and between 1b, 3b and 2b, 3b for Col I, Col III, TGF-β1, and VEGF mRNA expressions. ConclusionEPO had an additive effect with surgery on the injured tendon healing process in rats compared to the control groups biomechanically, histopathologically and with tissue protein mRNA expression. Clinical relevanceThis is the first experimental study to analyze the relationship between EPO treatment and the patellar tendon repair process by biomechanical, histopathological, and tendon tissue mRNA expression methodologies.

Reconstruction of Quadriceps Extensor Mechanism at Child, Three Months after “Sleeve Fracture of Patella”

Fractures of distal pole of patella are usually inadequate cured and most often unrecognised. Children between the third and sixth year have often been affected by this kind of fracture. This is one of the most frequent types of patella fracture that is found at skeletal immature persons. Injuries are often overlooked on the first medical examination and x-ray scanning is not properly read because relatively small part of bone can be seen while the greater part of patella is cartilaginous. It is necessary, in this case, to do detailed clinical examination. The case of unsuccessful conservatively cured fracture of distal patella pole, at ten years old boy, is shown here. This case lead to appearance of re fracture that happened during running after which the boy hasn’t seen orthopaedist for three months. Patella atlas and repressed distal fragment with ligament of patella have been appointed. Reconstructive surgery had been done and has been followed by intensive physical therapy in a period of three months. After treatment period results were; active and passive knee mobility, painless movement as well as returning back to sport activities. Even three months after injury it is possible to have successful reconstruction of re-fracture of distal patella pole at children’s age of ten.

Sagittal patellar tilt and concomitant quadriceps hypotrophy after tibial nailing.

The aim of the study was to analyse the patellofemoral alignment in the sagittal plane following tibial fracture surgery with intramedullary nailing and its relationship to parapatellar muscle status. The patellofemoral MRI results of 27 patients (15 males and 12 females) treated with locked intramedullary nailing following tibia shaft fracture were reviewed. The mean age of the patients was 41.8 (±15)years. The patella-patellar tendon angle (P-PT) and the distance between the inferior patellar pole and the tibial tubercle (DP-TT) were evaluated for both the operated extremity and the contralateral normal side. MRI assessment of the infrapatellar fat pad, quadriceps, sartorius, gracilis, semi-membranosus muscles and biceps muscles was also carried out. The correlation between the changes in skeletal muscle mass, the volume of the infrapatellar fat pad and the alterations in the DP-TT distances and P-PT angles were analysed. The quadriceps muscle cross-sectional diameter had a mean of 157.2mm(2) (115.6/319.5) in the operated extremity, and it was 193mm(2) (77.6/282.2) in the non-operated normal side (p=0.001). For the Gracilis muscle, the mean was 84.4mm(2) (19.7/171) at the operated extremity and 75.7mm(2) (26.9/238.2) on the normal side (p=0.05). The cross-sectional areas of the semi-membranosus, sartorius and biceps muscles in the operated and non-operated extremity were not noticeably different (n.s). The P-PT angle was 153° (129.7/156.4) in the operated extremity and 145.7° (137.6/163.4) in the non-operated normal extremity (p<0.05). While DP-TT distance was 11.4mm (9.4/20.4) in the operated extremity, it was 14.1mm (7.3/17.1) in the non-operated extremity (p=0.001). The correlation analyses revealed that the quadriceps hypotrophy negatively correlated (r=-0.4, p=0.02) with the P-PT angle but positively correlated with the increase in gracilis muscle volume (r=0.4, p=0.03). This study revealed that patellofemoral joint kinematics in the operated extremity was diminished in the sagittal plane correlating with the quadriceps muscle volume loss and gracilis muscle hypertrophy. The modalities focused on both preventing and treating the hypotrophy of the quadriceps muscle following the surgical treatment of tibial fracture, which may help to overcome this quite common pathology.

Tendinopathy Alters Cumulative Transverse Strain in the Patellar Tendon after Exercise

This research evaluated the effect of tendinopathy on the cumulative transverse strain response of the patellar tendon to a bout of resistive quadriceps exercise. Nine adults with unilateral patellar tendinopathy (age, 18.2 ± 0.7 yr; height, 1.92 ± 0.06 m; weight, 76.8 ± 6.8 kg) and 10 healthy adults free of knee pain (age, 17.8 ± 0.8 yr; height, 1.83 ± 0.05 m; weight, 73.2 ± 7.6 kg) underwent standardized sagittal sonograms (7.2-14 MHz linear array transducer) of both patellar tendons immediately before and after 45 repetitions of a double-leg decline squat exercise performed against a resistance of 145% body weight. Tendon thickness was determined 5 and 25 mm distal to the patellar pole. Transverse Hencky strain was calculated as the natural log of the ratio of post- to preexercise tendon thickness and expressed as percentage. Measures of tendon echogenicity were calculated within the superficial and deep aspects of each tendon site from grayscale profiles. Intratendinous microvessels were evaluated using power Doppler ultrasound. The cumulative transverse strain response to exercise in symptomatic tendinopathy was significantly lower than that in asymptomatic and healthy tendons (P < 0.05). There was also significant reduction (57%) in the area of microvascularity immediately after exercise (P = 0.05), which was positively correlated (r = 0.93, P < 0.05) with a Victorian Institute of Sport Assessment for patellar tendinopathy score. This study is the first to show that patellar tendinopathy is associated with altered morphological and mechanical response of the tendon to exercise, which is manifest by reduction in cumulative transverse strain and microvascularity, when present. Research directed toward identifying factors that influence the acute microvascular and transverse strain response of the patellar tendon to exercise in the various stages of tendinopathy is warranted.

Hoffa's fat pad disease: A study

Introduction: German surgeon by name Albert Hoffa in 1904 described the condition which was producing severe anterior knee pain was called Hoffa’s fat pad disease. This disease is commonly encountered in athletes after the second decade. The lowest age present in the literature with symptomatic Hoffa’s fat pad disease is ten years. Most common pathology in Hoffa’s fat pad disease is impingement of fat pad between anterior margin of tibia and intercondylar notch of femur. Here we are done an attempt to know the aetiology, diagnosis and management of the Hoffa’s fat pad disease. Materials and methods: 150 cases of knee joint pain were evaluated in our institute. 107 cases were suffering from medial margin pain, twenty nine cases from lateral margin, seven over and adjacent to ligamentum patella, three from inferior pole of patella, three from tibial tuberosity and one had pain at superior pole of patella. We studied seven patients suffering from Hoffa’s fat pad disease from April 2011 to December 2014 in our hospital. Inclusion criteria were age group between ten to sixty years irrespective of sex suffering from anterior knee pain with tenderness and swelling over and adjacent to the ligamentum patella. The exclusion criteria were age less than ten and more than sixty, pain at the suprapatellar region, inferior pole, superior pole of patella, at tibial tuberosity only, along medial and lateral margin of knee, popliteal fossa were excluded from our study. We have done a study to know the causes, how to diagnose the problem and management. Conclusion: Hoffa’s disease is common after second decade, rare in children. Usually it is seen in athletes. Squatting, running, climbing stairs, trauma and postsurgical scarring are the causes encountered in our study. Diagnosis is by history, clinical examination and radiological investigations like X-ray and Magnetic resonance imaging. Conservative management is the first line of treatment for three to four months and if it fails most of them were treated by complete excision of Hoffa’s fat pad through anterior arthrotomy. Keywords: Hoffa’s disease, Anterior knee pain, X-Ray, MRI, Arthrotomy

Bilateral Stress Fracture at the Inferior Pole of Patella in a Juvenile Athlete

Patellar fractures in children occur rarely in approximately 1% of all pediatric fractures and 57% of these are osteochondral or cartilaginous avulsion fractures, a type of sleeve fracture. They may be missed in diagnosis due to small bony fragment on simple radiographs, and they always occur ipsilaterally; however, only a few cases of bilateral patellar fracture of the inferior pole have been reported. We experienced an 11 year-old patient an athlete, who suffered repetitive minor trauma, with a stress fracture, which occurred at the inferior pole of the patella bilaterally, and we report on this unusual case with a literature review.

Inferior patellar pole fragmentation in children: just a normal variant?

Fragmentary ossification of the inferior patella is often dismissed as a normal variant in children younger than 10years of age. The purpose of this study was to determine whether fragmentary inferior patellar pole ossification is a normal variant or is associated with symptoms or signs of pathology using MRI and clinical exam findings as reference. A retrospective review was performed on 150 patients ages 5-10years who underwent 164 knee radiography and MRI exams (45.1% male, mean age: 7.8years). The presence or absence of inferior patellar pole fragmentation on radiography was correlated with the presence or absence of edema-like signal on MR images. Clinical notes were reviewed for the presence of symptoms or signs referable to the inferior patellar pole. These data were compared with a 1:1 age- and sex-matched control group without inferior pole fragmentation. Statistical analysis was performed using two-tailed t-tests. Forty of 164 (24.4%) knee radiographs showed fragmentary ossification of the inferior patella. Of these 40 knees, 62.5% (25/40) had edema-like signal of the inferior patellar bone marrow compared with 7.5% (3/40) of controls (P = 0.035). Patients with fragmentary ossification at the inferior patella had a significantly higher incidence of documented focal inferior patellar pain compared with controls (20% vs. 2.5%, P = 0.015). Inferior patellar pole fragmentation in children 5 to 10years of age may be associated with localized symptoms and bone marrow edema-like signal and should not be routinely dismissed as a normal variant of ossification.

"A 40-year-old female with painless, slow growing prepatellar mass".

A 40-year-old woman from India presented with a mass in the front of her left knee which had been present for 8 months. Local examination revealed a globular mass of approximate size 5cm×4cm×4cm in front of the lower pole of left patella. The patient was investigated with imaging studies and laboratory tests. Plain radiograph of the chest was normal. In addition, contrast enhanced Magnetic Resonance Imaging (MRI) of the left knee was performed. Based on the history, physical examination, laboratory and imaging studies, what is the differential diagnosis?

The limited use of a tourniquet during total knee arthroplasty: a randomized controlled trial.

Total knee arthroplasty (TKA) is commonly performed using a tourniquet. However, some studies have reported that several complications were associated with the use of a tourniquet in TKA. In this study we investigate whether the limited use of a tourniquet in TKA would reduce complications and facilitate postoperative recovery. Sixty patients were randomly divided into two groups (30 cases/group): group A using the tourniquet throughout the surgical procedure, and group B using the tourniquet starting from the cementation to the completion of the procedure. Operation time, total measured blood loss, and incidence of complications were all recorded. There was no significant difference in operation time, total measured blood loss, and hemoglobin concentration between the two groups. Incidence of postoperative complications in group B was significantly decreased in comparison to that in group A. The limb circumference at 10 cm above the superior patellar pole or below the inferior patellar pole and the pain score in group B were significantly decreased compared with that in group A at any time point. Range of motion in group B was significantly increased at three and 5 days postoperatively in comparison to that in group A. The limited use of a tourniquet in TKA provides the benefit of decreased limb swelling and knee joint pain while not compromising the operation time or blood loss and recovery. Level I (Therapeutic). NCT02102581.

Influence of wound drainage in primary total knee arthroplasty without tourniquet.

Although it remains the golden standard, several authors have questioned the role of pneumatic tourniquets in primary knee arthroplasty in recent studies. An intra-articular wound drainage is widely used in the field of total knee arthroplasty although the benefit of postoperative wound drainage is controversial in the literature. This study questioned whether the use of an intra-articular drain is an advance over the lack of a drain in total knee arthroplasty which is performed without a tourniquet. We documented the ROM, the knee circumference at the upper patellar pole pre-operatively and on days two, four and six postoperatively. The blood volume and loss was calculated. As surrogate parameter for wound healing we counted the number of days until no residual secretion was observed via the wound/drainage site. The results of our investigation showed a significantly better wound healing without the use of a drain. All other parameters revealed no significant differences. The data of this study demonstrate a faster wound healing without the use of a postoperative wound drain in primary total knee arthroplasty which is performed without a tourniquet. Other parameters could not show any significant differences thus indicating that a postoperative wound drain has no significant advantage and the risk of a retrograde bacterial colonisation is well documented. Based on these data we recommend performing a primary total knee arthroplasty without a postoperative drain if the procedure is done without a tourniquet.

Ipsilateral Patellar Distal Pole and Tibial Tubercle Avulsion Fractures in an Adolescent: A Case Report and Review of the Literature.

We present a case of simultaneous ipsilateral patellar distal pole and tibial tubercle avulsion fractures in an adolescent patient. While each entity is well documented when occurring in isolation, to the best of our knowledge, this is the first case in the medical literature of both injuries occurring simultaneously. The patient and his mother were informed that data concerning the case would be submitted for publication, and they provided consent. A fourteen-year-old healthy adolescent (with a body mass index of 23 kg/m2) presented to the emergency department following a fall forward onto a hyperflexed left knee. Immediate symptoms were pain in the knee and inability to bear weight. There was no relevant past or family history, and he had no prior history of fractures. Prior to the injury, he had been healthy with no history of pain in the anterior aspect of the knee or Osgood-Schlatter disease. On examination, there was a large effusion in the left knee, with tenderness at both the proximal and distal ends of the patellar tendon. The overlying skin was intact. Despite adequate analgesia, the patient was unable to perform a straight leg raise or extend the knee. The knee was stable in the coronal and sagittal planes. Radiographs (Figs. 1-A and 1-B) demonstrated an opacity distal to the patella, keeping with a sleeve-type avulsion fracture of the distal pole. The Insall-Salvati ratio was 1.8. The knee was placed in a temporary splint and surgery was recommended. Preoperative anteroposterior ( Fig. 1-A ) and cross-table lateral ( Fig. 1-B ) radiographs of the left knee. Both radiographs show an opacity distal to the patella, but the tibial tubercle appears relatively normal. Fig. 1-A Fig. 1-B The patient was taken to the operating room the following morning, and an arthrotomy was performed via a midline incision. Both medial and lateral retinacular disruption were noted. The distal patellar avulsion was evaluated; there was no substantial soft-tissue dissection, but we noted a multifragmentary extra-articular fracture …

Suture Anchor Repair for Superior Pole Patella Sleeve Fracture Involving the Undersurface of the Quadriceps Insertion

A 12-year-old boy fell on his flexed knee and was unable to actively extend the injured knee. Radiographs demonstrated a small osseous fragment at the superior pole of the patella and magnetic resonance imaging demonstrated the periosteal sleeve to be detached from the superior pole of the patella involving approximately three fourths of the undersurface of the quadriceps tendon footprint. This unusual variant of a patellar sleeve fracture was repaired using bioabsorbable suture anchors. Four months postoperatively, he had regained full mobility and strength of the injured knee. Prompt diagnosis aided with magnetic resonance imaging can help delineate the extent of injury. Surgical repair using a parapatellar arthrotomy without disrupting the most superficial fibers of the quadriceps mechanism is feasible and allows the patient to return to their functional activities in a short period.