The treatment of osteoarthritis of the knee in the young patient remains contentious. Several approaches have been described. It appears more and more that the knee joint should be considered as an “organ”. Indeed, as one intra-articular system fails, it brings injury and degeneration to other parts of the system so that the joint – organ – will fail inevitably. Alignment, stability, menisci and cartilage are the core ingredients in the knee joint – organ – to function. All however are secondary to the patients’ weight – obesity – and activity. These are not under orthopaedics surgeon’s control.
Dye1 and Dye and Chew’s2 envelope of function is today’s best comprehensive approach towards understanding this complicated but yet obvious combination. Stone et al’s paper,3 on the other hand, is addressing a particular issue in the knee joint. Their patient selection is very specific. Even though it includes only knees which have undergone a menisectomy and, additionally, often with a wide range of degeneration in the weight bearing compartments. These particular patients request a biological solution not wanting implant related alternatives or surgery to correct alignment. In his paper the common denominator is the meniscal allograft transplantation. In addition, an ‘à la carte’ number of operations have been performed like extensive cartilage grafting and stabilisation procedures. This ‘à la carte’ approach covers most of the potential mechanical issues within the knee, except for correction of alignment.
A recent meta-analysis4 of papers dealing with meniscal transplant surgery includes more than 1100 cases with both medial and lateral transplants. It is remarkable that only 368 patients had isolated meniscal transplant surgery. All others had various other associated procedures. This meta-analysis supports the fact that these young individuals, as in Stone’s study, often have a variety of conditions in their knee joint – organ – including malalignment and cartilage degeneration, as well as being of differing age and body habitus.
In this respect the combined importance of both stability and the meniscus has been investigated both in vivo5 as in vitro.6,7
Long term results after ACL repair (more than 25 years) have shown ligamentous reconstruction to be protective towards the articular cartilage in about 66% of the patients when the meniscus was intact.
In the knee which has undergone a partial menisectomy, degeneration occurred in 66% of the patients. Almost all patients with ACL deficiency deficient knee joint and menisectomy developed degenerative changes of the weight bearing cartilage.5
Papageorgiou et al7 have illustrated the interdependence of the medial meniscus and the ACL when the knee was subjected to an 134 N of anterior tibial load. With ACL deficiency the medial meniscal force increased up to threefold at 60° of flexion after medial menisectomy anterior tibial translation in the ACL deficient knee increased up to 5.8 mm. They have also examined the interdependence of the medial meniscus and the ACL graft. Following ACL reconstruction the forces on the medial meniscus could be restored to nearly normal levels for an externally applied load. Following medial menisectomy the in situ forces and the ACL graft increased up to 52% at 60° of flexion. Spang et al8 have also shown meniscal allografting and ligament repair to give each other return protection in an in vitro study.
Finally, in a clinical setting, various conditions and dysfunction of the knee appear to confront the orthopaedic surgeon. He (she) more often than not should consider the knee – organ - to be potentially affected by several conditions caused by failing systems inside the joint – organ. Thus, various approaches are needed.
Correct alignment is a basic requirement followed by stability of the knee, meniscal integrity and cartilage status.
Isolated single treatment may be efficacious in limited disease. However, in a progressive disease all elements of the knee – organ – will need to be addressed and treated.
1. Dye SF. The pathophysiology of patellofemoral pain: a tissue homeostasis perspective. Clin Orthop 2005;436:100-10.
2. Dye SF, Chew MH. Restoration of osseous homeostasis after anterior cruciate ligament reconstruction. Am J Sports Med. 1993;21:748-50.
3. Stone KR, Adelson WS, Pelsis JR, Walgenbach AW, Turek TJ. Long-term survival of concurrent meniscus allograft transplantation and repair of the articular cartilage: a prospective two- to 12-year follow-up report. J Bone Joint Surg [Br] 2010;92:941-8.
4. ElAttar M, Verdonk R, Almqvist KF, Verdonk PC. Twenty-Six Years of meniscal allograft transplantation: is it still experimental? A meta-analysis of 44 trials. Submitted to Am J Sports Med.
5. Pernin J, Verdonk P, Si Selmi TA, Massin P, Neyret P. Long-term follow-up of 24.5 years after intra-articular anterior cruciate ligament reconstruction with lateral extra-articular augmentation. Am J Sports Med 2010;38:1094-102.
6. Allen CR, Wong EK, Livesay GA, et al. Importance of the medial meniscus in the anterior cruciate ligament-deficient knee. J Orthop Res 2000;18:109-15.
7. Papageorgiou CD, Gil JE, Kanamori A, et al. The biomechanical interdependence between the anterior cruciate ligament replacement graft and the medial meniscus. Am J Sports Med 2001;29:226-31.
8. Spang JT, Dang ABC, Mazzocca A, et al. The effect of medial meniscectomy and meniscal allograft transplantation on knee and anterior cruciate ligament biomechanics. Arthroscopy 2010;26:192-201.
Verdonk R, Professor
Universitar Zeikenhuis, Gent, Belgium