Jump to content

Congenital Absence of the Anterior Cruciate Ligament

Original Editor - Dana Alhindawi

Top Contributors - Dana Alhindawi, Kim Jackson, Khloud Shreif and Carina Therese Magtibay  

Introduction

Congenital absence of the anterior cruciate ligament (ACL) is a rare condition, with a reported prevalence of 0.017 per 1000 live births[1]. First described by Giorgi in 1956 in a radiographic study[2]. It has since been reported either as an isolated anatomical entity or, more commonly, in association with other congenital lower extremity abnormalities. Such congenital dysplasia is unilateral, rarely being observed in both knee joints[3].

An Embryological Standpoint

It has been found that the fetal anterior cruciate ligament developed by 20 weeks of gestation, vascular invasion into the epiphysis at 24 weeks, and establishment of a secure epiphyseal attachment by 36 weeks [4]. It is assumed that the congenital anomaly that causes absence of ACL development is thought to express itself around the 7–8 postovulatory week [5].

Associated Abnormalities

ACL agenesis is often associated with other lower limb anomalies[6]:

  • Hypoplasia of the lateral femoral condyle.
  • Hypoplasia of the intercondylar eminence and the intercondylar notch.
  • Absent or abnormal menisci.
  • Congenital short femur.
  • There are defects in the fibular head and the fibular muscles.
  • Dislocation of the patella.

Classification System of the Three Types of Congenital Deficiency of the Cruciate Ligaments

There has been a classification system developed by Manner et al [7]:

  • Type I: Is characterized by hypoplasia or aplasia of the anterior cruciate ligament with a normal posterior cruciate ligament and it is the most common one.
  • Type II : Aplasia of the anterior cruciate ligament in combination with hypoplasia of the posterior cruciate ligament.
  • Type III: Aplasia of both cruciate ligaments.
Congenital-absence-of-anterior-cruciate-ligament222
Type I Absence of anterior cruciate ligament. Posterior cruciate ligament intact.


Clinical Presentation

The clinical presentation varies based on the degree of deformity and the associated congenital conditions present [8].

  • It is often obvious at birth when it when associated with a congenital knee dislocation
  • Shortening of the limb when combined with severe fibular hemimelia or other significant congenital deformity
  • Increasing knee instability
  • increasing valgus subluxation
  • Limb-length discrepancy or malalignment
Congenital knee dislocation.
knee valgus.



Physical Examination

A physical examination must be done on the entire lower extremity [8]

  • Measure hip range of motion and compare it to the opposite side.
  • A rotational profile of the lower extremities. This includes the foot progression angle, internal/external rotation of the hip, thigh-foot-axis, and other abnormalities of the foot.
  • Clinical leg-length discrepancy. This can be performed from the umbilicus to the ankle/foot, or from the greater trochanters to the ankle/foot. When measuring the clinical leg-length discrepancy, it is important to include the size of the foot in the measurement, as measuring to the medial malleolus distally may underestimate the true discrepancy, or wooden blocks can be placed under the shorter limb until the pelvis is levelled, which will show the global discrepancy of the extremity.
  • Lower extremity examination should include coronal plane alignment, especially valgus of the knee joint.
  • ACL laxity examination (Lachman test, pivot shift test, and anterior and posterior drawer tests).
  • Varus and valgus stability of the knee should be assessed in both full extension and 30° of flexion.

Imaging

Imaging of the lower extremity should include: [8]

  • Knee radiographs - to assess full-length standing anteroposterior (AP) alignment
  • MRI - to further characterize the involvement of both the anterior and posterior cruciate ligaments

How to Distinguish Between the Traumatic Loss and Congenital Absence of a Cruciate Ligament

Radiologists often find it difficult to distinguish between traumatic loss and congenital absence of a cruciate ligament. Cases show that if trauma is reported in a patient’s history and the contralateral knee is normal, and if arthroscopic and MRI reports do not focus on femoral intercondylar or zygomatic spinal deformities (X-rays show an abnormality of the sacrum, with only one bump in the sacrum, possibly a sign of cruciate ligament dysplasia), the correct diagnosis may be missed. Therefore, when using imaging to judge between congenital instability and post-traumatic instability, it shall be ascertained whether the joint bones in the knee are deformed. The differentiation of trauma and underdevelopment of one or two cruciate ligaments can be determined based on the difference in the gap width index and height and changes in the lateral and/or medial spinous processes of the tibia.[9]

Management

  • Conservative treatment such as strengthening the knee-related muscle for patients with no apparent symptoms or low frequency of pain and instability.[10]
  • Cruciate ligament reconstruction for patients with symptoms of instability either with or without walking pain but without knee joint deformity.[9]
  • Tibial osteotomy to correct the skeletal deformity for patients with bony knee deformities that prevent adding an anterior or posterior cruciate ligament without it being damaged and the cruciate ligament reconstruction can be considered.[9]

Physiotherapy Management

There is no specific physiotherapy rehabilitation protocol that addresses this condition clearly. The progression from one phase to another depends on tissue healing, type of surgery, and if it is combined with other syndromes or abnormalities.

Stage one (Protection) – post-operative protection of the graft (0-6)weeks

  • Decrease joint effusion to reduce pain and prevent quadriceps inhibition[11].
  • Bracing to protect the graft site by limiting varus and valgus stresses and restricting ROM[12].
  • Range of motionEarly range of motion has been proven in the literature in reducing post-surgical complications, and reaching full passive patellofemoral motion is important in this phase[13] .
  • Patellar mobilisations [14].
  • Isometric exercises for quadriceps[15].


Criteria for the progression from Phase I

Patient must achieve the below criteria in order to proceed to Phase 2 of the rehab[12]

  • Active terminal knee extension.
  • Active flexion to within 10° of the opposite knee.
  • Gait: partial weight bearing without assistive device.
  • Swelling within 0.5 cm of opposite knee.


Phase 2: Periodized Strength Development – Muscular Endurance (7-14 weeks)

  • Strengthening of major muscle groups and endurance based strength training program[16] [17].

This includes: wall squat holds (quad), total body resistance exercise, squats (quad), single leg huttle squats (quad), supine bridge with HS curl (hamstring), resisted lateral steps (glutes), and alternating lunge holds (quad).

Phase II progression criteria

Patient must achieve the below criteria in order to proceed to Phase 3 of the rehab [12]

  • Full active range of motion.
  • Single leg squat from 10 inch for 15 reps.


Phase 3: Periodized Strength Development – Muscular strength (15 – 21 weeks)

In this phase of rehabilitation, the rehab protocol must focus on building muscle strength and engage more in agility training.[12]

  • Regaining muscular strength
  • Running and agility progression should be implemented in this stage.


Return to activity or sport depends on the patient's performance and the required measures in various components from power, speed, strength, and agility.


Resources

The Pediatric Anterior Cruciate Ligament Evaluation and Management Strategies

POST-OPERATIVE CRITERION BASED REHABILITATION OF ACL REPAIRS: A CLINICAL COMMENTARY

Reference

  1. ↑ Degnan AJ, Kietz DA, Grudziak JS, Shah A. Bilateral absence of the cruciate ligaments with meniscal dysplasia: Unexpected diagnosis in a child with juvenile idiopathic arthritis. Clin Imaging. 2018 May-Jun;49:193-197.
  2. ↑ GIORGI B. Morphologic variations of the intercondylar eminence of the knee. Clin Orthop. 1956;8:209-17. .
  3. ↑ Barrett GR, Tomasin JD. Bilateral congenital absence of the anterior cruciate ligament. Orthopedics. 1988 Mar;11(3):431-4.
  4. ↑ Behr CT, Potter HG, Paletta GA Jr. The relationship of the femoral origin of the anterior cruciate ligament and the distal femoral physeal plate in the skeletally immature knee. An anatomic study. Am J Sports Med. 2001 Nov-Dec;29(6):781-7
  5. ↑ Berruto M, Gala L, Usellini E, Duci D, Marelli B. Congenital absence of the cruciate ligaments. Knee Surg Sports Traumatol Arthrosc. 2012;20(8):1622–5
  6. ↑ Silva A, Sampaio R. Anterior lateral meniscofemoral ligament with congenital absence of the ACL. Knee Surg Sports Traumatol Arthrosc. 2011 Feb;19(2):192-5.
  7. ↑ Manner HM, Radler C, Ganger R, Grill F. Dysplasia of the cruciate ligaments: radiographic assessment and classification. J Bone Joint Surg Am. 2006 Jan;88(1):130-7.
  8. ↑ 8.0 8.1 8.2 Beran, M.C., Samora, W.P., Klingele, K.E., Parikh, S.N. (2018). Congenital Absence of the Anterior Cruciate Ligament. In: Parikh, S. (eds) The Pediatric Anterior Cruciate Ligament. Springer.
  9. ↑ 9.0 9.1 9.2 Lu R, Zhu DP, Chen N, Sun H, Li ZH, Cao XW. How should congenital absence of cruciate ligaments be treated? A case report and literature review. World J Clin Cases. 2019 Oct 6;7(19):3082-3089.
  10. ↑ Gabos PG, El Rassi G, Pahys J. Knee reconstruction in syndromes with congenital absence of the anterior cruciate ligament. J Pediatr Orthop. 2005 Mar-Apr;25(2):210-4.
  11. ↑ Woo SL, Abramowitch SD, Kilger R, Liang R. Biomechanics of knee ligaments: injury, healing, and repair. J Biomech. 2006;39(1):1-20.
  12. ↑ 12.0 12.1 12.2 12.3 Wu J, Kator JL, Zarro M, Leong NL. Rehabilitation Principles to Consider for Anterior Cruciate Ligament Repair. Sports Health. 2022 May-Jun;14(3):424-432.
  13. ↑ NOYES, FRANK R. M.D.; MANGINE, ROBERT E. P.T., M.ED.; BARBER, SUE D. B.S.. The Early Treatment of Motion Complications After Reconstruction of the Anterior Cruciate Ligament. Clinical Orthopaedics and Related Research 277():p 217-228, April 1992.
  14. ↑ Noyes, F., Berrios-Torres, S., Barber-Westin, S. et al. Prevention of permanent arthrofibrosis after anterior cruciate ligament reconstruction alone or combined with associated procedures: a prospective study in 443 knees. Knee Surgery 8, 196–206 (2000).
  15. ↑ Lewek M, Rudolph K, Axe M, Snyder-Mackler L. The effect of insufficient quadriceps strength on gait after anterior cruciate ligament reconstruction. Clin Biomech (Bristol, Avon). 2002 Jan;17(1):56-63.
  16. ↑ Garber CE Blissmer B Deschenes MR. et al. Quantity and quality of exercise for developing and maintaining cardiorespiratory, musculoskeletal, and neuromotor fitness in apparently healthy adults: guidance for prescribing exercise. Med Sci Sports Exerc. 2011;43(7):1334-1359
  17. ↑ American College of Sports Medicine. American College of Sports Medicine position stand. Progression models in resistance training for healthy adults. Med Sci Sports Exerc. 2009 Mar;41(3):687-708
Retrieved from "https://www.physio-pedia.com/w/index.php?title=Congenital_Absence_of_the_Anterior_Cruciate_Ligament&oldid=362925"